• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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  */
48 static bool nfs4_disable_idmapping = true;
49 module_param(nfs4_disable_idmapping, bool, 0644);
50 MODULE_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 struct 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 
76 static void
ent_init(struct cache_head * cnew,struct cache_head * citm)77 ent_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 
89 static void
ent_put(struct kref * ref)90 ent_put(struct kref *ref)
91 {
92 	struct ent *map = container_of(ref, struct ent, h.ref);
93 	kfree_rcu(map, rcu_head);
94 }
95 
96 static struct cache_head *
ent_alloc(void)97 ent_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 
110 static uint32_t
idtoname_hash(struct ent * ent)111 idtoname_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 
125 static int
idtoname_upcall(struct cache_detail * cd,struct cache_head * h)126 idtoname_upcall(struct cache_detail *cd, struct cache_head *h)
127 {
128 	return sunrpc_cache_pipe_upcall_timeout(cd, h);
129 }
130 
131 static void
idtoname_request(struct cache_detail * cd,struct cache_head * ch,char ** bpp,int * blen)132 idtoname_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 
146 static int
idtoname_match(struct cache_head * ca,struct cache_head * cb)147 idtoname_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 
156 static int
idtoname_show(struct seq_file * m,struct cache_detail * cd,struct cache_head * h)157 idtoname_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 
175 static void
warn_no_idmapd(struct cache_detail * detail,int has_died)176 warn_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 
183 static int         idtoname_parse(struct cache_detail *, char *, int);
184 static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
185 static struct ent *idtoname_update(struct cache_detail *, struct ent *,
186 				   struct ent *);
187 
188 static 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 
204 static int
idtoname_parse(struct cache_detail * cd,char * buf,int buflen)205 idtoname_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;
267 out:
268 	kfree(buf1);
269 	return error;
270 }
271 
272 static struct ent *
idtoname_lookup(struct cache_detail * cd,struct ent * item)273 idtoname_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 
283 static struct ent *
idtoname_update(struct cache_detail * cd,struct ent * new,struct ent * old)284 idtoname_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 
299 static inline int
nametoid_hash(struct ent * ent)300 nametoid_hash(struct ent *ent)
301 {
302 	return hash_str(ent->name, ENT_HASHBITS);
303 }
304 
305 static int
nametoid_upcall(struct cache_detail * cd,struct cache_head * h)306 nametoid_upcall(struct cache_detail *cd, struct cache_head *h)
307 {
308 	return sunrpc_cache_pipe_upcall_timeout(cd, h);
309 }
310 
311 static void
nametoid_request(struct cache_detail * cd,struct cache_head * ch,char ** bpp,int * blen)312 nametoid_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 
324 static int
nametoid_match(struct cache_head * ca,struct cache_head * cb)325 nametoid_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 
334 static int
nametoid_show(struct seq_file * m,struct cache_detail * cd,struct cache_head * h)335 nametoid_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 
353 static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
354 static struct ent *nametoid_update(struct cache_detail *, struct ent *,
355 				   struct ent *);
356 static int         nametoid_parse(struct cache_detail *, char *, int);
357 
358 static 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 
374 static int
nametoid_parse(struct cache_detail * cd,char * buf,int buflen)375 nametoid_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;
431 out:
432 	kfree(buf1);
433 	return (error);
434 }
435 
436 
437 static struct ent *
nametoid_lookup(struct cache_detail * cd,struct ent * item)438 nametoid_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 
448 static struct ent *
nametoid_update(struct cache_detail * cd,struct ent * new,struct ent * old)449 nametoid_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 
463 int
nfsd_idmap_init(struct net * net)464 nfsd_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 
485 destroy_nametoid_cache:
486 	cache_destroy_net(nn->nametoid_cache, net);
487 unregister_idtoname_cache:
488 	cache_unregister_net(nn->idtoname_cache, net);
489 destroy_idtoname_cache:
490 	cache_destroy_net(nn->idtoname_cache, net);
491 	return rv;
492 }
493 
494 void
nfsd_idmap_shutdown(struct net * net)495 nfsd_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 
505 static int
idmap_lookup(struct svc_rqst * rqstp,struct ent * (* lookup_fn)(struct cache_detail *,struct ent *),struct ent * key,struct cache_detail * detail,struct ent ** item)506 idmap_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 
528 static char *
rqst_authname(struct svc_rqst * rqstp)529 rqst_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 
537 static __be32
idmap_name_to_id(struct svc_rqst * rqstp,int type,const char * name,u32 namelen,u32 * id)538 idmap_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 
encode_ascii_id(struct xdr_stream * xdr,u32 id)562 static __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 
idmap_id_to_name(struct xdr_stream * xdr,struct svc_rqst * rqstp,int type,u32 id)576 static __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 
603 static bool
numeric_name_to_id(struct svc_rqst * rqstp,int type,const char * name,u32 namelen,u32 * id)604 numeric_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 
619 static __be32
do_name_to_id(struct svc_rqst * rqstp,int type,const char * name,u32 namelen,u32 * id)620 do_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 
encode_name_from_id(struct xdr_stream * xdr,struct svc_rqst * rqstp,int type,u32 id)632 static __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
nfsd_map_name_to_uid(struct svc_rqst * rqstp,const char * name,size_t namelen,kuid_t * uid)641 nfsd_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
nfsd_map_name_to_gid(struct svc_rqst * rqstp,const char * name,size_t namelen,kgid_t * gid)658 nfsd_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 
nfsd4_encode_user(struct xdr_stream * xdr,struct svc_rqst * rqstp,kuid_t uid)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 
nfsd4_encode_group(struct xdr_stream * xdr,struct svc_rqst * rqstp,kgid_t gid)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 }
687