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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};
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}