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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
62#define IDMAP_TYPE_USER 0
63#define IDMAP_TYPE_GROUP 1
64
65struct ent {
66 struct cache_head h;
67 int type; /* User / Group */
68 u32 id;
69 char name[IDMAP_NAMESZ];
70 char authname[IDMAP_NAMESZ];
71};
72
73/* Common entry handling */
74
75#define ENT_HASHBITS 8
76#define ENT_HASHMAX (1 << ENT_HASHBITS)
77
78static void
79ent_init(struct cache_head *cnew, struct cache_head *citm)
80{
81 struct ent *new = container_of(cnew, struct ent, h);
82 struct ent *itm = container_of(citm, struct ent, h);
83
84 new->id = itm->id;
85 new->type = itm->type;
86
87 strlcpy(new->name, itm->name, sizeof(new->name));
88 strlcpy(new->authname, itm->authname, sizeof(new->name));
89}
90
91static void
92ent_put(struct kref *ref)
93{
94 struct ent *map = container_of(ref, struct ent, h.ref);
95 kfree(map);
96}
97
98static struct cache_head *
99ent_alloc(void)
100{
101 struct ent *e = kmalloc(sizeof(*e), GFP_KERNEL);
102 if (e)
103 return &e->h;
104 else
105 return NULL;
106}
107
108/*
109 * ID -> Name cache
110 */
111
112static uint32_t
113idtoname_hash(struct ent *ent)
114{
115 uint32_t hash;
116
117 hash = hash_str(ent->authname, ENT_HASHBITS);
118 hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
119
120 /* Flip LSB for user/group */
121 if (ent->type == IDMAP_TYPE_GROUP)
122 hash ^= 1;
123
124 return hash;
125}
126
127static void
128idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
129 int *blen)
130{
131 struct ent *ent = container_of(ch, struct ent, h);
132 char idstr[11];
133
134 qword_add(bpp, blen, ent->authname);
135 snprintf(idstr, sizeof(idstr), "%u", ent->id);
136 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
137 qword_add(bpp, blen, idstr);
138
139 (*bpp)[-1] = '\n';
140}
141
142static int
143idtoname_match(struct cache_head *ca, struct cache_head *cb)
144{
145 struct ent *a = container_of(ca, struct ent, h);
146 struct ent *b = container_of(cb, struct ent, h);
147
148 return (a->id == b->id && a->type == b->type &&
149 strcmp(a->authname, b->authname) == 0);
150}
151
152static int
153idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
154{
155 struct ent *ent;
156
157 if (h == NULL) {
158 seq_puts(m, "#domain type id [name]\n");
159 return 0;
160 }
161 ent = container_of(h, struct ent, h);
162 seq_printf(m, "%s %s %u", ent->authname,
163 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
164 ent->id);
165 if (test_bit(CACHE_VALID, &h->flags))
166 seq_printf(m, " %s", ent->name);
167 seq_printf(m, "\n");
168 return 0;
169}
170
171static void
172warn_no_idmapd(struct cache_detail *detail, int has_died)
173{
174 printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
175 has_died ? "died" : "not been started");
176}
177
178
179static int idtoname_parse(struct cache_detail *, char *, int);
180static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
181static struct ent *idtoname_update(struct cache_detail *, struct ent *,
182 struct ent *);
183
184static struct cache_detail idtoname_cache_template = {
185 .owner = THIS_MODULE,
186 .hash_size = ENT_HASHMAX,
187 .name = "nfs4.idtoname",
188 .cache_put = ent_put,
189 .cache_request = idtoname_request,
190 .cache_parse = idtoname_parse,
191 .cache_show = idtoname_show,
192 .warn_no_listener = warn_no_idmapd,
193 .match = idtoname_match,
194 .init = ent_init,
195 .update = ent_init,
196 .alloc = ent_alloc,
197};
198
199static int
200idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
201{
202 struct ent ent, *res;
203 char *buf1, *bp;
204 int len;
205 int error = -EINVAL;
206
207 if (buf[buflen - 1] != '\n')
208 return (-EINVAL);
209 buf[buflen - 1]= '\0';
210
211 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
212 if (buf1 == NULL)
213 return (-ENOMEM);
214
215 memset(&ent, 0, sizeof(ent));
216
217 /* Authentication name */
218 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
219 goto out;
220 memcpy(ent.authname, buf1, sizeof(ent.authname));
221
222 /* Type */
223 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
224 goto out;
225 ent.type = strcmp(buf1, "user") == 0 ?
226 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
227
228 /* ID */
229 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
230 goto out;
231 ent.id = simple_strtoul(buf1, &bp, 10);
232 if (bp == buf1)
233 goto out;
234
235 /* expiry */
236 ent.h.expiry_time = get_expiry(&buf);
237 if (ent.h.expiry_time == 0)
238 goto out;
239
240 error = -ENOMEM;
241 res = idtoname_lookup(cd, &ent);
242 if (!res)
243 goto out;
244
245 /* Name */
246 error = -EINVAL;
247 len = qword_get(&buf, buf1, PAGE_SIZE);
248 if (len < 0)
249 goto out;
250 if (len == 0)
251 set_bit(CACHE_NEGATIVE, &ent.h.flags);
252 else if (len >= IDMAP_NAMESZ)
253 goto out;
254 else
255 memcpy(ent.name, buf1, sizeof(ent.name));
256 error = -ENOMEM;
257 res = idtoname_update(cd, &ent, res);
258 if (res == NULL)
259 goto out;
260
261 cache_put(&res->h, cd);
262
263 error = 0;
264out:
265 kfree(buf1);
266
267 return error;
268}
269
270
271static struct ent *
272idtoname_lookup(struct cache_detail *cd, struct ent *item)
273{
274 struct cache_head *ch = sunrpc_cache_lookup(cd, &item->h,
275 idtoname_hash(item));
276 if (ch)
277 return container_of(ch, struct ent, h);
278 else
279 return NULL;
280}
281
282static struct ent *
283idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
284{
285 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
286 idtoname_hash(new));
287 if (ch)
288 return container_of(ch, struct ent, h);
289 else
290 return NULL;
291}
292
293
294/*
295 * Name -> ID cache
296 */
297
298static inline int
299nametoid_hash(struct ent *ent)
300{
301 return hash_str(ent->name, ENT_HASHBITS);
302}
303
304static void
305nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
306 int *blen)
307{
308 struct ent *ent = container_of(ch, struct ent, h);
309
310 qword_add(bpp, blen, ent->authname);
311 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
312 qword_add(bpp, blen, ent->name);
313
314 (*bpp)[-1] = '\n';
315}
316
317static int
318nametoid_match(struct cache_head *ca, struct cache_head *cb)
319{
320 struct ent *a = container_of(ca, struct ent, h);
321 struct ent *b = container_of(cb, struct ent, h);
322
323 return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
324 strcmp(a->authname, b->authname) == 0);
325}
326
327static int
328nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
329{
330 struct ent *ent;
331
332 if (h == NULL) {
333 seq_puts(m, "#domain type name [id]\n");
334 return 0;
335 }
336 ent = container_of(h, struct ent, h);
337 seq_printf(m, "%s %s %s", ent->authname,
338 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
339 ent->name);
340 if (test_bit(CACHE_VALID, &h->flags))
341 seq_printf(m, " %u", ent->id);
342 seq_printf(m, "\n");
343 return 0;
344}
345
346static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
347static struct ent *nametoid_update(struct cache_detail *, struct ent *,
348 struct ent *);
349static int nametoid_parse(struct cache_detail *, char *, int);
350
351static struct cache_detail nametoid_cache_template = {
352 .owner = THIS_MODULE,
353 .hash_size = ENT_HASHMAX,
354 .name = "nfs4.nametoid",
355 .cache_put = ent_put,
356 .cache_request = nametoid_request,
357 .cache_parse = nametoid_parse,
358 .cache_show = nametoid_show,
359 .warn_no_listener = warn_no_idmapd,
360 .match = nametoid_match,
361 .init = ent_init,
362 .update = ent_init,
363 .alloc = ent_alloc,
364};
365
366static int
367nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
368{
369 struct ent ent, *res;
370 char *buf1;
371 int error = -EINVAL;
372
373 if (buf[buflen - 1] != '\n')
374 return (-EINVAL);
375 buf[buflen - 1]= '\0';
376
377 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
378 if (buf1 == NULL)
379 return (-ENOMEM);
380
381 memset(&ent, 0, sizeof(ent));
382
383 /* Authentication name */
384 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
385 goto out;
386 memcpy(ent.authname, buf1, sizeof(ent.authname));
387
388 /* Type */
389 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
390 goto out;
391 ent.type = strcmp(buf1, "user") == 0 ?
392 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
393
394 /* Name */
395 error = qword_get(&buf, buf1, PAGE_SIZE);
396 if (error <= 0 || error >= IDMAP_NAMESZ)
397 goto out;
398 memcpy(ent.name, buf1, sizeof(ent.name));
399
400 /* expiry */
401 ent.h.expiry_time = get_expiry(&buf);
402 if (ent.h.expiry_time == 0)
403 goto out;
404
405 /* ID */
406 error = get_int(&buf, &ent.id);
407 if (error == -EINVAL)
408 goto out;
409 if (error == -ENOENT)
410 set_bit(CACHE_NEGATIVE, &ent.h.flags);
411
412 error = -ENOMEM;
413 res = nametoid_lookup(cd, &ent);
414 if (res == NULL)
415 goto out;
416 res = nametoid_update(cd, &ent, res);
417 if (res == NULL)
418 goto out;
419
420 cache_put(&res->h, cd);
421 error = 0;
422out:
423 kfree(buf1);
424
425 return (error);
426}
427
428
429static struct ent *
430nametoid_lookup(struct cache_detail *cd, struct ent *item)
431{
432 struct cache_head *ch = sunrpc_cache_lookup(cd, &item->h,
433 nametoid_hash(item));
434 if (ch)
435 return container_of(ch, struct ent, h);
436 else
437 return NULL;
438}
439
440static struct ent *
441nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
442{
443 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
444 nametoid_hash(new));
445 if (ch)
446 return container_of(ch, struct ent, h);
447 else
448 return NULL;
449}
450
451/*
452 * Exported API
453 */
454
455int
456nfsd_idmap_init(struct net *net)
457{
458 int rv;
459 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
460
461 nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
462 if (IS_ERR(nn->idtoname_cache))
463 return PTR_ERR(nn->idtoname_cache);
464 rv = cache_register_net(nn->idtoname_cache, net);
465 if (rv)
466 goto destroy_idtoname_cache;
467 nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
468 if (IS_ERR(nn->nametoid_cache)) {
469 rv = PTR_ERR(nn->nametoid_cache);
470 goto unregister_idtoname_cache;
471 }
472 rv = cache_register_net(nn->nametoid_cache, net);
473 if (rv)
474 goto destroy_nametoid_cache;
475 return 0;
476
477destroy_nametoid_cache:
478 cache_destroy_net(nn->nametoid_cache, net);
479unregister_idtoname_cache:
480 cache_unregister_net(nn->idtoname_cache, net);
481destroy_idtoname_cache:
482 cache_destroy_net(nn->idtoname_cache, net);
483 return rv;
484}
485
486void
487nfsd_idmap_shutdown(struct net *net)
488{
489 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
490
491 cache_unregister_net(nn->idtoname_cache, net);
492 cache_unregister_net(nn->nametoid_cache, net);
493 cache_destroy_net(nn->idtoname_cache, net);
494 cache_destroy_net(nn->nametoid_cache, net);
495}
496
497static int
498idmap_lookup(struct svc_rqst *rqstp,
499 struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
500 struct ent *key, struct cache_detail *detail, struct ent **item)
501{
502 int ret;
503
504 *item = lookup_fn(detail, key);
505 if (!*item)
506 return -ENOMEM;
507 retry:
508 ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
509
510 if (ret == -ETIMEDOUT) {
511 struct ent *prev_item = *item;
512 *item = lookup_fn(detail, key);
513 if (*item != prev_item)
514 goto retry;
515 cache_put(&(*item)->h, detail);
516 }
517 return ret;
518}
519
520static char *
521rqst_authname(struct svc_rqst *rqstp)
522{
523 struct auth_domain *clp;
524
525 clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
526 return clp->name;
527}
528
529static __be32
530idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
531 u32 *id)
532{
533 struct ent *item, key = {
534 .type = type,
535 };
536 int ret;
537 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
538
539 if (namelen + 1 > sizeof(key.name))
540 return nfserr_badowner;
541 memcpy(key.name, name, namelen);
542 key.name[namelen] = '\0';
543 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
544 ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
545 if (ret == -ENOENT)
546 return nfserr_badowner;
547 if (ret)
548 return nfserrno(ret);
549 *id = item->id;
550 cache_put(&item->h, nn->nametoid_cache);
551 return 0;
552}
553
554static __be32 encode_ascii_id(u32 id, __be32 **p, int *buflen)
555{
556 char buf[11];
557 int len;
558 int bytes;
559
560 len = sprintf(buf, "%u", id);
561 bytes = 4 + (XDR_QUADLEN(len) << 2);
562 if (bytes > *buflen)
563 return nfserr_resource;
564 *p = xdr_encode_opaque(*p, buf, len);
565 *buflen -= bytes;
566 return 0;
567}
568
569static __be32 idmap_id_to_name(struct svc_rqst *rqstp, int type, u32 id, __be32 **p, int *buflen)
570{
571 struct ent *item, key = {
572 .id = id,
573 .type = type,
574 };
575 int ret;
576 int bytes;
577 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
578
579 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
580 ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
581 if (ret == -ENOENT)
582 return encode_ascii_id(id, p, buflen);
583 if (ret)
584 return nfserrno(ret);
585 ret = strlen(item->name);
586 WARN_ON_ONCE(ret > IDMAP_NAMESZ);
587 bytes = 4 + (XDR_QUADLEN(ret) << 2);
588 if (bytes > *buflen)
589 return nfserr_resource;
590 *p = xdr_encode_opaque(*p, item->name, ret);
591 *buflen -= bytes;
592 cache_put(&item->h, nn->idtoname_cache);
593 return 0;
594}
595
596static bool
597numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
598{
599 int ret;
600 char buf[11];
601
602 if (namelen + 1 > sizeof(buf))
603 /* too long to represent a 32-bit id: */
604 return false;
605 /* Just to make sure it's null-terminated: */
606 memcpy(buf, name, namelen);
607 buf[namelen] = '\0';
608 ret = kstrtouint(buf, 10, id);
609 return ret == 0;
610}
611
612static __be32
613do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
614{
615 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
616 if (numeric_name_to_id(rqstp, type, name, namelen, id))
617 return 0;
618 /*
619 * otherwise, fall through and try idmapping, for
620 * backwards compatibility with clients sending names:
621 */
622 return idmap_name_to_id(rqstp, type, name, namelen, id);
623}
624
625static __be32 encode_name_from_id(struct svc_rqst *rqstp, int type, u32 id, __be32 **p, int *buflen)
626{
627 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
628 return encode_ascii_id(id, p, buflen);
629 return idmap_id_to_name(rqstp, type, id, p, buflen);
630}
631
632__be32
633nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
634 kuid_t *uid)
635{
636 __be32 status;
637 u32 id = -1;
638 status = do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, &id);
639 *uid = make_kuid(&init_user_ns, id);
640 if (!uid_valid(*uid))
641 status = nfserr_badowner;
642 return status;
643}
644
645__be32
646nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
647 kgid_t *gid)
648{
649 __be32 status;
650 u32 id = -1;
651 status = do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, &id);
652 *gid = make_kgid(&init_user_ns, id);
653 if (!gid_valid(*gid))
654 status = nfserr_badowner;
655 return status;
656}
657
658__be32 nfsd4_encode_user(struct svc_rqst *rqstp, kuid_t uid, __be32 **p, int *buflen)
659{
660 u32 id = from_kuid(&init_user_ns, uid);
661 return encode_name_from_id(rqstp, IDMAP_TYPE_USER, id, p, buflen);
662}
663
664__be32 nfsd4_encode_group(struct svc_rqst *rqstp, kgid_t gid, __be32 **p, int *buflen)
665{
666 u32 id = from_kgid(&init_user_ns, gid);
667 return encode_name_from_id(rqstp, IDMAP_TYPE_GROUP, id, p, buflen);
668}
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 int
126idtoname_upcall(struct cache_detail *cd, struct cache_head *h)
127{
128 return sunrpc_cache_pipe_upcall_timeout(cd, h);
129}
130
131static void
132idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
133 int *blen)
134{
135 struct ent *ent = container_of(ch, struct ent, h);
136 char idstr[11];
137
138 qword_add(bpp, blen, ent->authname);
139 snprintf(idstr, sizeof(idstr), "%u", ent->id);
140 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
141 qword_add(bpp, blen, idstr);
142
143 (*bpp)[-1] = '\n';
144}
145
146static int
147idtoname_match(struct cache_head *ca, struct cache_head *cb)
148{
149 struct ent *a = container_of(ca, struct ent, h);
150 struct ent *b = container_of(cb, struct ent, h);
151
152 return (a->id == b->id && a->type == b->type &&
153 strcmp(a->authname, b->authname) == 0);
154}
155
156static int
157idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
158{
159 struct ent *ent;
160
161 if (h == NULL) {
162 seq_puts(m, "#domain type id [name]\n");
163 return 0;
164 }
165 ent = container_of(h, struct ent, h);
166 seq_printf(m, "%s %s %u", ent->authname,
167 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
168 ent->id);
169 if (test_bit(CACHE_VALID, &h->flags))
170 seq_printf(m, " %s", ent->name);
171 seq_putc(m, '\n');
172 return 0;
173}
174
175static void
176warn_no_idmapd(struct cache_detail *detail, int has_died)
177{
178 printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
179 has_died ? "died" : "not been started");
180}
181
182
183static int idtoname_parse(struct cache_detail *, char *, int);
184static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
185static struct ent *idtoname_update(struct cache_detail *, struct ent *,
186 struct ent *);
187
188static const struct cache_detail idtoname_cache_template = {
189 .owner = THIS_MODULE,
190 .hash_size = ENT_HASHMAX,
191 .name = "nfs4.idtoname",
192 .cache_put = ent_put,
193 .cache_upcall = idtoname_upcall,
194 .cache_request = idtoname_request,
195 .cache_parse = idtoname_parse,
196 .cache_show = idtoname_show,
197 .warn_no_listener = warn_no_idmapd,
198 .match = idtoname_match,
199 .init = ent_init,
200 .update = ent_init,
201 .alloc = ent_alloc,
202};
203
204static int
205idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
206{
207 struct ent ent, *res;
208 char *buf1, *bp;
209 int len;
210 int error = -EINVAL;
211
212 if (buf[buflen - 1] != '\n')
213 return (-EINVAL);
214 buf[buflen - 1]= '\0';
215
216 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
217 if (buf1 == NULL)
218 return (-ENOMEM);
219
220 memset(&ent, 0, sizeof(ent));
221
222 /* Authentication name */
223 len = qword_get(&buf, buf1, PAGE_SIZE);
224 if (len <= 0 || len >= IDMAP_NAMESZ)
225 goto out;
226 memcpy(ent.authname, buf1, sizeof(ent.authname));
227
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;
233
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;
240
241 /* expiry */
242 ent.h.expiry_time = get_expiry(&buf);
243 if (ent.h.expiry_time == 0)
244 goto out;
245
246 error = -ENOMEM;
247 res = idtoname_lookup(cd, &ent);
248 if (!res)
249 goto out;
250
251 /* Name */
252 error = -EINVAL;
253 len = qword_get(&buf, buf1, PAGE_SIZE);
254 if (len < 0 || len >= IDMAP_NAMESZ)
255 goto out;
256 if (len == 0)
257 set_bit(CACHE_NEGATIVE, &ent.h.flags);
258 else
259 memcpy(ent.name, buf1, sizeof(ent.name));
260 error = -ENOMEM;
261 res = idtoname_update(cd, &ent, res);
262 if (res == NULL)
263 goto out;
264
265 cache_put(&res->h, cd);
266 error = 0;
267out:
268 kfree(buf1);
269 return error;
270}
271
272static struct ent *
273idtoname_lookup(struct cache_detail *cd, struct ent *item)
274{
275 struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
276 idtoname_hash(item));
277 if (ch)
278 return container_of(ch, struct ent, h);
279 else
280 return NULL;
281}
282
283static struct ent *
284idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
285{
286 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
287 idtoname_hash(new));
288 if (ch)
289 return container_of(ch, struct ent, h);
290 else
291 return NULL;
292}
293
294
295/*
296 * Name -> ID cache
297 */
298
299static inline int
300nametoid_hash(struct ent *ent)
301{
302 return hash_str(ent->name, ENT_HASHBITS);
303}
304
305static int
306nametoid_upcall(struct cache_detail *cd, struct cache_head *h)
307{
308 return sunrpc_cache_pipe_upcall_timeout(cd, h);
309}
310
311static void
312nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
313 int *blen)
314{
315 struct ent *ent = container_of(ch, struct ent, h);
316
317 qword_add(bpp, blen, ent->authname);
318 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
319 qword_add(bpp, blen, ent->name);
320
321 (*bpp)[-1] = '\n';
322}
323
324static int
325nametoid_match(struct cache_head *ca, struct cache_head *cb)
326{
327 struct ent *a = container_of(ca, struct ent, h);
328 struct ent *b = container_of(cb, struct ent, h);
329
330 return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
331 strcmp(a->authname, b->authname) == 0);
332}
333
334static int
335nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
336{
337 struct ent *ent;
338
339 if (h == NULL) {
340 seq_puts(m, "#domain type name [id]\n");
341 return 0;
342 }
343 ent = container_of(h, struct ent, h);
344 seq_printf(m, "%s %s %s", ent->authname,
345 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
346 ent->name);
347 if (test_bit(CACHE_VALID, &h->flags))
348 seq_printf(m, " %u", ent->id);
349 seq_putc(m, '\n');
350 return 0;
351}
352
353static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
354static struct ent *nametoid_update(struct cache_detail *, struct ent *,
355 struct ent *);
356static int nametoid_parse(struct cache_detail *, char *, int);
357
358static const struct cache_detail nametoid_cache_template = {
359 .owner = THIS_MODULE,
360 .hash_size = ENT_HASHMAX,
361 .name = "nfs4.nametoid",
362 .cache_put = ent_put,
363 .cache_upcall = nametoid_upcall,
364 .cache_request = nametoid_request,
365 .cache_parse = nametoid_parse,
366 .cache_show = nametoid_show,
367 .warn_no_listener = warn_no_idmapd,
368 .match = nametoid_match,
369 .init = ent_init,
370 .update = ent_init,
371 .alloc = ent_alloc,
372};
373
374static int
375nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
376{
377 struct ent ent, *res;
378 char *buf1;
379 int len, error = -EINVAL;
380
381 if (buf[buflen - 1] != '\n')
382 return (-EINVAL);
383 buf[buflen - 1]= '\0';
384
385 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
386 if (buf1 == NULL)
387 return (-ENOMEM);
388
389 memset(&ent, 0, sizeof(ent));
390
391 /* Authentication name */
392 len = qword_get(&buf, buf1, PAGE_SIZE);
393 if (len <= 0 || len >= IDMAP_NAMESZ)
394 goto out;
395 memcpy(ent.authname, buf1, sizeof(ent.authname));
396
397 /* Type */
398 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
399 goto out;
400 ent.type = strcmp(buf1, "user") == 0 ?
401 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
402
403 /* Name */
404 len = qword_get(&buf, buf1, PAGE_SIZE);
405 if (len <= 0 || len >= IDMAP_NAMESZ)
406 goto out;
407 memcpy(ent.name, buf1, sizeof(ent.name));
408
409 /* expiry */
410 ent.h.expiry_time = get_expiry(&buf);
411 if (ent.h.expiry_time == 0)
412 goto out;
413
414 /* ID */
415 error = get_int(&buf, &ent.id);
416 if (error == -EINVAL)
417 goto out;
418 if (error == -ENOENT)
419 set_bit(CACHE_NEGATIVE, &ent.h.flags);
420
421 error = -ENOMEM;
422 res = nametoid_lookup(cd, &ent);
423 if (res == NULL)
424 goto out;
425 res = nametoid_update(cd, &ent, res);
426 if (res == NULL)
427 goto out;
428
429 cache_put(&res->h, cd);
430 error = 0;
431out:
432 kfree(buf1);
433 return (error);
434}
435
436
437static struct ent *
438nametoid_lookup(struct cache_detail *cd, struct ent *item)
439{
440 struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
441 nametoid_hash(item));
442 if (ch)
443 return container_of(ch, struct ent, h);
444 else
445 return NULL;
446}
447
448static struct ent *
449nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
450{
451 struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
452 nametoid_hash(new));
453 if (ch)
454 return container_of(ch, struct ent, h);
455 else
456 return NULL;
457}
458
459/*
460 * Exported API
461 */
462
463int
464nfsd_idmap_init(struct net *net)
465{
466 int rv;
467 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
468
469 nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
470 if (IS_ERR(nn->idtoname_cache))
471 return PTR_ERR(nn->idtoname_cache);
472 rv = cache_register_net(nn->idtoname_cache, net);
473 if (rv)
474 goto destroy_idtoname_cache;
475 nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
476 if (IS_ERR(nn->nametoid_cache)) {
477 rv = PTR_ERR(nn->nametoid_cache);
478 goto unregister_idtoname_cache;
479 }
480 rv = cache_register_net(nn->nametoid_cache, net);
481 if (rv)
482 goto destroy_nametoid_cache;
483 return 0;
484
485destroy_nametoid_cache:
486 cache_destroy_net(nn->nametoid_cache, net);
487unregister_idtoname_cache:
488 cache_unregister_net(nn->idtoname_cache, net);
489destroy_idtoname_cache:
490 cache_destroy_net(nn->idtoname_cache, net);
491 return rv;
492}
493
494void
495nfsd_idmap_shutdown(struct net *net)
496{
497 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
498
499 cache_unregister_net(nn->idtoname_cache, net);
500 cache_unregister_net(nn->nametoid_cache, net);
501 cache_destroy_net(nn->idtoname_cache, net);
502 cache_destroy_net(nn->nametoid_cache, net);
503}
504
505static int
506idmap_lookup(struct svc_rqst *rqstp,
507 struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
508 struct ent *key, struct cache_detail *detail, struct ent **item)
509{
510 int ret;
511
512 *item = lookup_fn(detail, key);
513 if (!*item)
514 return -ENOMEM;
515 retry:
516 ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
517
518 if (ret == -ETIMEDOUT) {
519 struct ent *prev_item = *item;
520 *item = lookup_fn(detail, key);
521 if (*item != prev_item)
522 goto retry;
523 cache_put(&(*item)->h, detail);
524 }
525 return ret;
526}
527
528static char *
529rqst_authname(struct svc_rqst *rqstp)
530{
531 struct auth_domain *clp;
532
533 clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
534 return clp->name;
535}
536
537static __be32
538idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
539 u32 *id)
540{
541 struct ent *item, key = {
542 .type = type,
543 };
544 int ret;
545 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
546
547 if (namelen + 1 > sizeof(key.name))
548 return nfserr_badowner;
549 memcpy(key.name, name, namelen);
550 key.name[namelen] = '\0';
551 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
552 ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
553 if (ret == -ENOENT)
554 return nfserr_badowner;
555 if (ret)
556 return nfserrno(ret);
557 *id = item->id;
558 cache_put(&item->h, nn->nametoid_cache);
559 return 0;
560}
561
562static __be32 encode_ascii_id(struct xdr_stream *xdr, u32 id)
563{
564 char buf[11];
565 int len;
566 __be32 *p;
567
568 len = sprintf(buf, "%u", id);
569 p = xdr_reserve_space(xdr, len + 4);
570 if (!p)
571 return nfserr_resource;
572 p = xdr_encode_opaque(p, buf, len);
573 return 0;
574}
575
576static __be32 idmap_id_to_name(struct xdr_stream *xdr,
577 struct svc_rqst *rqstp, int type, u32 id)
578{
579 struct ent *item, key = {
580 .id = id,
581 .type = type,
582 };
583 __be32 *p;
584 int ret;
585 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
586
587 strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
588 ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
589 if (ret == -ENOENT)
590 return encode_ascii_id(xdr, id);
591 if (ret)
592 return nfserrno(ret);
593 ret = strlen(item->name);
594 WARN_ON_ONCE(ret > IDMAP_NAMESZ);
595 p = xdr_reserve_space(xdr, ret + 4);
596 if (!p)
597 return nfserr_resource;
598 p = xdr_encode_opaque(p, item->name, ret);
599 cache_put(&item->h, nn->idtoname_cache);
600 return 0;
601}
602
603static bool
604numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
605{
606 int ret;
607 char buf[11];
608
609 if (namelen + 1 > sizeof(buf))
610 /* too long to represent a 32-bit id: */
611 return false;
612 /* Just to make sure it's null-terminated: */
613 memcpy(buf, name, namelen);
614 buf[namelen] = '\0';
615 ret = kstrtouint(buf, 10, id);
616 return ret == 0;
617}
618
619static __be32
620do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
621{
622 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
623 if (numeric_name_to_id(rqstp, type, name, namelen, id))
624 return 0;
625 /*
626 * otherwise, fall through and try idmapping, for
627 * backwards compatibility with clients sending names:
628 */
629 return idmap_name_to_id(rqstp, type, name, namelen, id);
630}
631
632static __be32 encode_name_from_id(struct xdr_stream *xdr,
633 struct svc_rqst *rqstp, int type, u32 id)
634{
635 if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
636 return encode_ascii_id(xdr, id);
637 return idmap_id_to_name(xdr, rqstp, type, id);
638}
639
640__be32
641nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
642 kuid_t *uid)
643{
644 __be32 status;
645 u32 id = -1;
646
647 if (name == NULL || namelen == 0)
648 return nfserr_inval;
649
650 status = do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, &id);
651 *uid = make_kuid(nfsd_user_namespace(rqstp), id);
652 if (!uid_valid(*uid))
653 status = nfserr_badowner;
654 return status;
655}
656
657__be32
658nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
659 kgid_t *gid)
660{
661 __be32 status;
662 u32 id = -1;
663
664 if (name == NULL || namelen == 0)
665 return nfserr_inval;
666
667 status = do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, &id);
668 *gid = make_kgid(nfsd_user_namespace(rqstp), id);
669 if (!gid_valid(*gid))
670 status = nfserr_badowner;
671 return status;
672}
673
674__be32 nfsd4_encode_user(struct xdr_stream *xdr, struct svc_rqst *rqstp,
675 kuid_t uid)
676{
677 u32 id = from_kuid_munged(nfsd_user_namespace(rqstp), uid);
678 return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_USER, id);
679}
680
681__be32 nfsd4_encode_group(struct xdr_stream *xdr, struct svc_rqst *rqstp,
682 kgid_t gid)
683{
684 u32 id = from_kgid_munged(nfsd_user_namespace(rqstp), gid);
685 return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_GROUP, id);
686}