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v3.5.6
  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	uid_t             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_upcall(struct cache_detail *cd, struct cache_head *ch)
144{
145	return sunrpc_cache_pipe_upcall(cd, ch, idtoname_request);
146}
147
148static int
149idtoname_match(struct cache_head *ca, struct cache_head *cb)
150{
151	struct ent *a = container_of(ca, struct ent, h);
152	struct ent *b = container_of(cb, struct ent, h);
153
154	return (a->id == b->id && a->type == b->type &&
155	    strcmp(a->authname, b->authname) == 0);
156}
157
158static int
159idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
160{
161	struct ent *ent;
162
163	if (h == NULL) {
164		seq_puts(m, "#domain type id [name]\n");
165		return 0;
166	}
167	ent = container_of(h, struct ent, h);
168	seq_printf(m, "%s %s %u", ent->authname,
169			ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
170			ent->id);
171	if (test_bit(CACHE_VALID, &h->flags))
172		seq_printf(m, " %s", ent->name);
173	seq_printf(m, "\n");
174	return 0;
175}
176
177static void
178warn_no_idmapd(struct cache_detail *detail, int has_died)
179{
180	printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
181			has_died ? "died" : "not been started");
182}
183
184
185static int         idtoname_parse(struct cache_detail *, char *, int);
186static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
187static struct ent *idtoname_update(struct cache_detail *, struct ent *,
188				   struct ent *);
189
190static struct cache_detail idtoname_cache_template = {
191	.owner		= THIS_MODULE,
192	.hash_size	= ENT_HASHMAX,
193	.name		= "nfs4.idtoname",
194	.cache_put	= ent_put,
195	.cache_upcall	= idtoname_upcall,
 
196	.cache_parse	= idtoname_parse,
197	.cache_show	= idtoname_show,
198	.warn_no_listener = warn_no_idmapd,
199	.match		= idtoname_match,
200	.init		= ent_init,
201	.update		= ent_init,
202	.alloc		= ent_alloc,
203};
204
205static int
206idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
207{
208	struct ent ent, *res;
209	char *buf1, *bp;
210	int len;
211	int error = -EINVAL;
212
213	if (buf[buflen - 1] != '\n')
214		return (-EINVAL);
215	buf[buflen - 1]= '\0';
216
217	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
218	if (buf1 == NULL)
219		return (-ENOMEM);
220
221	memset(&ent, 0, sizeof(ent));
222
223	/* Authentication name */
224	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
 
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)
255		goto out;
256	if (len == 0)
257		set_bit(CACHE_NEGATIVE, &ent.h.flags);
258	else if (len >= IDMAP_NAMESZ)
259		goto out;
260	else
261		memcpy(ent.name, buf1, sizeof(ent.name));
262	error = -ENOMEM;
263	res = idtoname_update(cd, &ent, res);
264	if (res == NULL)
265		goto out;
266
267	cache_put(&res->h, cd);
268
269	error = 0;
270out:
271	kfree(buf1);
272
273	return error;
274}
275
276
277static struct ent *
278idtoname_lookup(struct cache_detail *cd, struct ent *item)
279{
280	struct cache_head *ch = sunrpc_cache_lookup(cd, &item->h,
281						    idtoname_hash(item));
282	if (ch)
283		return container_of(ch, struct ent, h);
284	else
285		return NULL;
286}
287
288static struct ent *
289idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
290{
291	struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
292						    idtoname_hash(new));
293	if (ch)
294		return container_of(ch, struct ent, h);
295	else
296		return NULL;
297}
298
299
300/*
301 * Name -> ID cache
302 */
303
304static inline int
305nametoid_hash(struct ent *ent)
306{
307	return hash_str(ent->name, ENT_HASHBITS);
308}
309
 
 
 
 
 
 
310static void
311nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
312    int *blen)
313{
314 	struct ent *ent = container_of(ch, struct ent, h);
315
316	qword_add(bpp, blen, ent->authname);
317	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
318	qword_add(bpp, blen, ent->name);
319
320	(*bpp)[-1] = '\n';
321}
322
323static int
324nametoid_upcall(struct cache_detail *cd, struct cache_head *ch)
325{
326	return sunrpc_cache_pipe_upcall(cd, ch, nametoid_request);
327}
328
329static int
330nametoid_match(struct cache_head *ca, struct cache_head *cb)
331{
332	struct ent *a = container_of(ca, struct ent, h);
333	struct ent *b = container_of(cb, struct ent, h);
334
335	return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
336	    strcmp(a->authname, b->authname) == 0);
337}
338
339static int
340nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
341{
342	struct ent *ent;
343
344	if (h == NULL) {
345		seq_puts(m, "#domain type name [id]\n");
346		return 0;
347	}
348	ent = container_of(h, struct ent, h);
349	seq_printf(m, "%s %s %s", ent->authname,
350			ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
351			ent->name);
352	if (test_bit(CACHE_VALID, &h->flags))
353		seq_printf(m, " %u", ent->id);
354	seq_printf(m, "\n");
355	return 0;
356}
357
358static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
359static struct ent *nametoid_update(struct cache_detail *, struct ent *,
360				   struct ent *);
361static int         nametoid_parse(struct cache_detail *, char *, int);
362
363static struct cache_detail nametoid_cache_template = {
364	.owner		= THIS_MODULE,
365	.hash_size	= ENT_HASHMAX,
366	.name		= "nfs4.nametoid",
367	.cache_put	= ent_put,
368	.cache_upcall	= nametoid_upcall,
 
369	.cache_parse	= nametoid_parse,
370	.cache_show	= nametoid_show,
371	.warn_no_listener = warn_no_idmapd,
372	.match		= nametoid_match,
373	.init		= ent_init,
374	.update		= ent_init,
375	.alloc		= ent_alloc,
376};
377
378static int
379nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
380{
381	struct ent ent, *res;
382	char *buf1;
383	int error = -EINVAL;
384
385	if (buf[buflen - 1] != '\n')
386		return (-EINVAL);
387	buf[buflen - 1]= '\0';
388
389	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
390	if (buf1 == NULL)
391		return (-ENOMEM);
392
393	memset(&ent, 0, sizeof(ent));
394
395	/* Authentication name */
396	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
 
397		goto out;
398	memcpy(ent.authname, buf1, sizeof(ent.authname));
399
400	/* Type */
401	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
402		goto out;
403	ent.type = strcmp(buf1, "user") == 0 ?
404		IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
405
406	/* Name */
407	error = qword_get(&buf, buf1, PAGE_SIZE);
408	if (error <= 0 || error >= IDMAP_NAMESZ)
409		goto out;
410	memcpy(ent.name, buf1, sizeof(ent.name));
411
412	/* expiry */
413	ent.h.expiry_time = get_expiry(&buf);
414	if (ent.h.expiry_time == 0)
415		goto out;
416
417	/* ID */
418	error = get_int(&buf, &ent.id);
419	if (error == -EINVAL)
420		goto out;
421	if (error == -ENOENT)
422		set_bit(CACHE_NEGATIVE, &ent.h.flags);
423
424	error = -ENOMEM;
425	res = nametoid_lookup(cd, &ent);
426	if (res == NULL)
427		goto out;
428	res = nametoid_update(cd, &ent, res);
429	if (res == NULL)
430		goto out;
431
432	cache_put(&res->h, cd);
433	error = 0;
434out:
435	kfree(buf1);
436
437	return (error);
438}
439
440
441static struct ent *
442nametoid_lookup(struct cache_detail *cd, struct ent *item)
443{
444	struct cache_head *ch = sunrpc_cache_lookup(cd, &item->h,
445						    nametoid_hash(item));
446	if (ch)
447		return container_of(ch, struct ent, h);
448	else
449		return NULL;
450}
451
452static struct ent *
453nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
454{
455	struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
456						    nametoid_hash(new));
457	if (ch)
458		return container_of(ch, struct ent, h);
459	else
460		return NULL;
461}
462
463/*
464 * Exported API
465 */
466
467int
468nfsd_idmap_init(struct net *net)
469{
470	int rv;
471	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
472
473	nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
474	if (IS_ERR(nn->idtoname_cache))
475		return PTR_ERR(nn->idtoname_cache);
476	rv = cache_register_net(nn->idtoname_cache, net);
477	if (rv)
478		goto destroy_idtoname_cache;
479	nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
480	if (IS_ERR(nn->nametoid_cache)) {
481		rv = PTR_ERR(nn->idtoname_cache);
482		goto unregister_idtoname_cache;
483	}
484	rv = cache_register_net(nn->nametoid_cache, net);
485	if (rv)
486		goto destroy_nametoid_cache;
487	return 0;
488
489destroy_nametoid_cache:
490	cache_destroy_net(nn->nametoid_cache, net);
491unregister_idtoname_cache:
492	cache_unregister_net(nn->idtoname_cache, net);
493destroy_idtoname_cache:
494	cache_destroy_net(nn->idtoname_cache, net);
495	return rv;
496}
497
498void
499nfsd_idmap_shutdown(struct net *net)
500{
501	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
502
503	cache_unregister_net(nn->idtoname_cache, net);
504	cache_unregister_net(nn->nametoid_cache, net);
505	cache_destroy_net(nn->idtoname_cache, net);
506	cache_destroy_net(nn->nametoid_cache, net);
507}
508
509static int
510idmap_lookup(struct svc_rqst *rqstp,
511		struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
512		struct ent *key, struct cache_detail *detail, struct ent **item)
513{
514	int ret;
515
516	*item = lookup_fn(detail, key);
517	if (!*item)
518		return -ENOMEM;
519 retry:
520	ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
521
522	if (ret == -ETIMEDOUT) {
523		struct ent *prev_item = *item;
524		*item = lookup_fn(detail, key);
525		if (*item != prev_item)
526			goto retry;
527		cache_put(&(*item)->h, detail);
528	}
529	return ret;
530}
531
532static char *
533rqst_authname(struct svc_rqst *rqstp)
534{
535	struct auth_domain *clp;
536
537	clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
538	return clp->name;
539}
540
541static __be32
542idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
543		uid_t *id)
544{
545	struct ent *item, key = {
546		.type = type,
547	};
548	int ret;
549	struct nfsd_net *nn = net_generic(rqstp->rq_xprt->xpt_net, nfsd_net_id);
550
551	if (namelen + 1 > sizeof(key.name))
552		return nfserr_badowner;
553	memcpy(key.name, name, namelen);
554	key.name[namelen] = '\0';
555	strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
556	ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
557	if (ret == -ENOENT)
558		return nfserr_badowner;
559	if (ret)
560		return nfserrno(ret);
561	*id = item->id;
562	cache_put(&item->h, nn->nametoid_cache);
563	return 0;
564}
565
566static int
567idmap_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
568{
569	struct ent *item, key = {
570		.id = id,
571		.type = type,
572	};
 
573	int ret;
574	struct nfsd_net *nn = net_generic(rqstp->rq_xprt->xpt_net, nfsd_net_id);
575
576	strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
577	ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
578	if (ret == -ENOENT)
579		return sprintf(name, "%u", id);
580	if (ret)
581		return ret;
582	ret = strlen(item->name);
583	BUG_ON(ret > IDMAP_NAMESZ);
584	memcpy(name, item->name, ret);
 
 
 
585	cache_put(&item->h, nn->idtoname_cache);
586	return ret;
587}
588
589static bool
590numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, uid_t *id)
591{
592	int ret;
593	char buf[11];
594
595	if (namelen + 1 > sizeof(buf))
596		/* too long to represent a 32-bit id: */
597		return false;
598	/* Just to make sure it's null-terminated: */
599	memcpy(buf, name, namelen);
600	buf[namelen] = '\0';
601	ret = kstrtouint(name, 10, id);
602	return ret == 0;
603}
604
605static __be32
606do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, uid_t *id)
607{
608	if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
609		if (numeric_name_to_id(rqstp, type, name, namelen, id))
610			return 0;
611		/*
612		 * otherwise, fall through and try idmapping, for
613		 * backwards compatibility with clients sending names:
614		 */
615	return idmap_name_to_id(rqstp, type, name, namelen, id);
616}
617
618static int
619do_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name)
620{
621	if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
622		return sprintf(name, "%u", id);
623	return idmap_id_to_name(rqstp, type, id, name);
624}
625
626__be32
627nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
628		__u32 *id)
629{
630	return do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
 
 
 
 
 
 
 
 
 
 
631}
632
633__be32
634nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
635		__u32 *id)
636{
637	return do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
 
 
 
 
 
 
 
 
 
 
638}
639
640int
641nfsd_map_uid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
642{
643	return do_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
 
644}
645
646int
647nfsd_map_gid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
648{
649	return do_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);
 
650}
v6.8
  1/*
  2 *  Mapping of UID/GIDs to name and vice versa.
  3 *
  4 *  Copyright (c) 2002, 2003 The Regents of the University of
  5 *  Michigan.  All rights reserved.
  6 *
  7 *  Marius Aamodt Eriksen <marius@umich.edu>
  8 *
  9 *  Redistribution and use in source and binary forms, with or without
 10 *  modification, are permitted provided that the following conditions
 11 *  are met:
 12 *
 13 *  1. Redistributions of source code must retain the above copyright
 14 *     notice, this list of conditions and the following disclaimer.
 15 *  2. Redistributions in binary form must reproduce the above copyright
 16 *     notice, this list of conditions and the following disclaimer in the
 17 *     documentation and/or other materials provided with the distribution.
 18 *  3. Neither the name of the University nor the names of its
 19 *     contributors may be used to endorse or promote products derived
 20 *     from this software without specific prior written permission.
 21 *
 22 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 23 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 24 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 25 *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 26 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 27 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 28 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 29 *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 30 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 31 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 32 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 33 */
 34
 35#include <linux/module.h>
 36#include <linux/seq_file.h>
 37#include <linux/sched.h>
 38#include <linux/slab.h>
 39#include <linux/sunrpc/svc_xprt.h>
 40#include <net/net_namespace.h>
 41#include "idmap.h"
 42#include "nfsd.h"
 43#include "netns.h"
 44#include "vfs.h"
 45
 46/*
 47 * Turn off idmapping when using AUTH_SYS.
 48 */
 49static bool nfs4_disable_idmapping = true;
 50module_param(nfs4_disable_idmapping, bool, 0644);
 51MODULE_PARM_DESC(nfs4_disable_idmapping,
 52		"Turn off server's NFSv4 idmapping when using 'sec=sys'");
 53
 54/*
 55 * Cache entry
 56 */
 57
 58/*
 59 * XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
 60 * that.
 61 */
 62
 
 
 
 63struct ent {
 64	struct cache_head h;
 65	int               type;		       /* User / Group */
 66	u32               id;
 67	char              name[IDMAP_NAMESZ];
 68	char              authname[IDMAP_NAMESZ];
 69	struct rcu_head	  rcu_head;
 70};
 71
 72/* Common entry handling */
 73
 74#define ENT_HASHBITS          8
 75#define ENT_HASHMAX           (1 << ENT_HASHBITS)
 76
 77static void
 78ent_init(struct cache_head *cnew, struct cache_head *citm)
 79{
 80	struct ent *new = container_of(cnew, struct ent, h);
 81	struct ent *itm = container_of(citm, struct ent, h);
 82
 83	new->id = itm->id;
 84	new->type = itm->type;
 85
 86	strscpy(new->name, itm->name, sizeof(new->name));
 87	strscpy(new->authname, itm->authname, sizeof(new->authname));
 88}
 89
 90static void
 91ent_put(struct kref *ref)
 92{
 93	struct ent *map = container_of(ref, struct ent, h.ref);
 94	kfree_rcu(map, rcu_head);
 95}
 96
 97static struct cache_head *
 98ent_alloc(void)
 99{
100	struct ent *e = kmalloc(sizeof(*e), GFP_KERNEL);
101	if (e)
102		return &e->h;
103	else
104		return NULL;
105}
106
107/*
108 * ID -> Name cache
109 */
110
111static uint32_t
112idtoname_hash(struct ent *ent)
113{
114	uint32_t hash;
115
116	hash = hash_str(ent->authname, ENT_HASHBITS);
117	hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
118
119	/* Flip LSB for user/group */
120	if (ent->type == IDMAP_TYPE_GROUP)
121		hash ^= 1;
122
123	return hash;
124}
125
126static int
127idtoname_upcall(struct cache_detail *cd, struct cache_head *h)
128{
129	return sunrpc_cache_pipe_upcall_timeout(cd, h);
130}
131
132static void
133idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
134    int *blen)
135{
136 	struct ent *ent = container_of(ch, struct ent, h);
137	char idstr[11];
138
139	qword_add(bpp, blen, ent->authname);
140	snprintf(idstr, sizeof(idstr), "%u", ent->id);
141	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
142	qword_add(bpp, blen, idstr);
143
144	(*bpp)[-1] = '\n';
145}
146
147static int
 
 
 
 
 
 
148idtoname_match(struct cache_head *ca, struct cache_head *cb)
149{
150	struct ent *a = container_of(ca, struct ent, h);
151	struct ent *b = container_of(cb, struct ent, h);
152
153	return (a->id == b->id && a->type == b->type &&
154	    strcmp(a->authname, b->authname) == 0);
155}
156
157static int
158idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
159{
160	struct ent *ent;
161
162	if (h == NULL) {
163		seq_puts(m, "#domain type id [name]\n");
164		return 0;
165	}
166	ent = container_of(h, struct ent, h);
167	seq_printf(m, "%s %s %u", ent->authname,
168			ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
169			ent->id);
170	if (test_bit(CACHE_VALID, &h->flags))
171		seq_printf(m, " %s", ent->name);
172	seq_putc(m, '\n');
173	return 0;
174}
175
176static void
177warn_no_idmapd(struct cache_detail *detail, int has_died)
178{
179	printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
180			has_died ? "died" : "not been started");
181}
182
183
184static int         idtoname_parse(struct cache_detail *, char *, int);
185static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
186static struct ent *idtoname_update(struct cache_detail *, struct ent *,
187				   struct ent *);
188
189static const struct cache_detail idtoname_cache_template = {
190	.owner		= THIS_MODULE,
191	.hash_size	= ENT_HASHMAX,
192	.name		= "nfs4.idtoname",
193	.cache_put	= ent_put,
194	.cache_upcall	= idtoname_upcall,
195	.cache_request	= idtoname_request,
196	.cache_parse	= idtoname_parse,
197	.cache_show	= idtoname_show,
198	.warn_no_listener = warn_no_idmapd,
199	.match		= idtoname_match,
200	.init		= ent_init,
201	.update		= ent_init,
202	.alloc		= ent_alloc,
203};
204
205static int
206idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
207{
208	struct ent ent, *res;
209	char *buf1, *bp;
210	int len;
211	int error = -EINVAL;
212
213	if (buf[buflen - 1] != '\n')
214		return (-EINVAL);
215	buf[buflen - 1]= '\0';
216
217	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
218	if (buf1 == NULL)
219		return (-ENOMEM);
220
221	memset(&ent, 0, sizeof(ent));
222
223	/* Authentication name */
224	len = qword_get(&buf, buf1, PAGE_SIZE);
225	if (len <= 0 || len >= IDMAP_NAMESZ)
226		goto out;
227	memcpy(ent.authname, buf1, sizeof(ent.authname));
228
229	/* Type */
230	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
231		goto out;
232	ent.type = strcmp(buf1, "user") == 0 ?
233		IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
234
235	/* ID */
236	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
237		goto out;
238	ent.id = simple_strtoul(buf1, &bp, 10);
239	if (bp == buf1)
240		goto out;
241
242	/* expiry */
243	error = get_expiry(&buf, &ent.h.expiry_time);
244	if (error)
245		goto out;
246
247	error = -ENOMEM;
248	res = idtoname_lookup(cd, &ent);
249	if (!res)
250		goto out;
251
252	/* Name */
253	error = -EINVAL;
254	len = qword_get(&buf, buf1, PAGE_SIZE);
255	if (len < 0 || len >= IDMAP_NAMESZ)
256		goto out;
257	if (len == 0)
258		set_bit(CACHE_NEGATIVE, &ent.h.flags);
 
 
259	else
260		memcpy(ent.name, buf1, sizeof(ent.name));
261	error = -ENOMEM;
262	res = idtoname_update(cd, &ent, res);
263	if (res == NULL)
264		goto out;
265
266	cache_put(&res->h, cd);
 
267	error = 0;
268out:
269	kfree(buf1);
 
270	return error;
271}
272
 
273static struct ent *
274idtoname_lookup(struct cache_detail *cd, struct ent *item)
275{
276	struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
277							idtoname_hash(item));
278	if (ch)
279		return container_of(ch, struct ent, h);
280	else
281		return NULL;
282}
283
284static struct ent *
285idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
286{
287	struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
288						    idtoname_hash(new));
289	if (ch)
290		return container_of(ch, struct ent, h);
291	else
292		return NULL;
293}
294
295
296/*
297 * Name -> ID cache
298 */
299
300static inline int
301nametoid_hash(struct ent *ent)
302{
303	return hash_str(ent->name, ENT_HASHBITS);
304}
305
306static int
307nametoid_upcall(struct cache_detail *cd, struct cache_head *h)
308{
309	return sunrpc_cache_pipe_upcall_timeout(cd, h);
310}
311
312static void
313nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
314    int *blen)
315{
316 	struct ent *ent = container_of(ch, struct ent, h);
317
318	qword_add(bpp, blen, ent->authname);
319	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
320	qword_add(bpp, blen, ent->name);
321
322	(*bpp)[-1] = '\n';
323}
324
325static int
 
 
 
 
 
 
326nametoid_match(struct cache_head *ca, struct cache_head *cb)
327{
328	struct ent *a = container_of(ca, struct ent, h);
329	struct ent *b = container_of(cb, struct ent, h);
330
331	return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
332	    strcmp(a->authname, b->authname) == 0);
333}
334
335static int
336nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
337{
338	struct ent *ent;
339
340	if (h == NULL) {
341		seq_puts(m, "#domain type name [id]\n");
342		return 0;
343	}
344	ent = container_of(h, struct ent, h);
345	seq_printf(m, "%s %s %s", ent->authname,
346			ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
347			ent->name);
348	if (test_bit(CACHE_VALID, &h->flags))
349		seq_printf(m, " %u", ent->id);
350	seq_putc(m, '\n');
351	return 0;
352}
353
354static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
355static struct ent *nametoid_update(struct cache_detail *, struct ent *,
356				   struct ent *);
357static int         nametoid_parse(struct cache_detail *, char *, int);
358
359static const struct cache_detail nametoid_cache_template = {
360	.owner		= THIS_MODULE,
361	.hash_size	= ENT_HASHMAX,
362	.name		= "nfs4.nametoid",
363	.cache_put	= ent_put,
364	.cache_upcall	= nametoid_upcall,
365	.cache_request	= nametoid_request,
366	.cache_parse	= nametoid_parse,
367	.cache_show	= nametoid_show,
368	.warn_no_listener = warn_no_idmapd,
369	.match		= nametoid_match,
370	.init		= ent_init,
371	.update		= ent_init,
372	.alloc		= ent_alloc,
373};
374
375static int
376nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
377{
378	struct ent ent, *res;
379	char *buf1;
380	int len, error = -EINVAL;
381
382	if (buf[buflen - 1] != '\n')
383		return (-EINVAL);
384	buf[buflen - 1]= '\0';
385
386	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
387	if (buf1 == NULL)
388		return (-ENOMEM);
389
390	memset(&ent, 0, sizeof(ent));
391
392	/* Authentication name */
393	len = qword_get(&buf, buf1, PAGE_SIZE);
394	if (len <= 0 || len >= IDMAP_NAMESZ)
395		goto out;
396	memcpy(ent.authname, buf1, sizeof(ent.authname));
397
398	/* Type */
399	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
400		goto out;
401	ent.type = strcmp(buf1, "user") == 0 ?
402		IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
403
404	/* Name */
405	len = qword_get(&buf, buf1, PAGE_SIZE);
406	if (len <= 0 || len >= IDMAP_NAMESZ)
407		goto out;
408	memcpy(ent.name, buf1, sizeof(ent.name));
409
410	/* expiry */
411	error = get_expiry(&buf, &ent.h.expiry_time);
412	if (error)
413		goto out;
414
415	/* ID */
416	error = get_int(&buf, &ent.id);
417	if (error == -EINVAL)
418		goto out;
419	if (error == -ENOENT)
420		set_bit(CACHE_NEGATIVE, &ent.h.flags);
421
422	error = -ENOMEM;
423	res = nametoid_lookup(cd, &ent);
424	if (res == NULL)
425		goto out;
426	res = nametoid_update(cd, &ent, res);
427	if (res == NULL)
428		goto out;
429
430	cache_put(&res->h, cd);
431	error = 0;
432out:
433	kfree(buf1);
 
434	return (error);
435}
436
437
438static struct ent *
439nametoid_lookup(struct cache_detail *cd, struct ent *item)
440{
441	struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
442							nametoid_hash(item));
443	if (ch)
444		return container_of(ch, struct ent, h);
445	else
446		return NULL;
447}
448
449static struct ent *
450nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
451{
452	struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
453						    nametoid_hash(new));
454	if (ch)
455		return container_of(ch, struct ent, h);
456	else
457		return NULL;
458}
459
460/*
461 * Exported API
462 */
463
464int
465nfsd_idmap_init(struct net *net)
466{
467	int rv;
468	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
469
470	nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
471	if (IS_ERR(nn->idtoname_cache))
472		return PTR_ERR(nn->idtoname_cache);
473	rv = cache_register_net(nn->idtoname_cache, net);
474	if (rv)
475		goto destroy_idtoname_cache;
476	nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
477	if (IS_ERR(nn->nametoid_cache)) {
478		rv = PTR_ERR(nn->nametoid_cache);
479		goto unregister_idtoname_cache;
480	}
481	rv = cache_register_net(nn->nametoid_cache, net);
482	if (rv)
483		goto destroy_nametoid_cache;
484	return 0;
485
486destroy_nametoid_cache:
487	cache_destroy_net(nn->nametoid_cache, net);
488unregister_idtoname_cache:
489	cache_unregister_net(nn->idtoname_cache, net);
490destroy_idtoname_cache:
491	cache_destroy_net(nn->idtoname_cache, net);
492	return rv;
493}
494
495void
496nfsd_idmap_shutdown(struct net *net)
497{
498	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
499
500	cache_unregister_net(nn->idtoname_cache, net);
501	cache_unregister_net(nn->nametoid_cache, net);
502	cache_destroy_net(nn->idtoname_cache, net);
503	cache_destroy_net(nn->nametoid_cache, net);
504}
505
506static int
507idmap_lookup(struct svc_rqst *rqstp,
508		struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
509		struct ent *key, struct cache_detail *detail, struct ent **item)
510{
511	int ret;
512
513	*item = lookup_fn(detail, key);
514	if (!*item)
515		return -ENOMEM;
516 retry:
517	ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
518
519	if (ret == -ETIMEDOUT) {
520		struct ent *prev_item = *item;
521		*item = lookup_fn(detail, key);
522		if (*item != prev_item)
523			goto retry;
524		cache_put(&(*item)->h, detail);
525	}
526	return ret;
527}
528
529static char *
530rqst_authname(struct svc_rqst *rqstp)
531{
532	struct auth_domain *clp;
533
534	clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
535	return clp->name;
536}
537
538static __be32
539idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
540		u32 *id)
541{
542	struct ent *item, key = {
543		.type = type,
544	};
545	int ret;
546	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
547
548	if (namelen + 1 > sizeof(key.name))
549		return nfserr_badowner;
550	memcpy(key.name, name, namelen);
551	key.name[namelen] = '\0';
552	strscpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
553	ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
554	if (ret == -ENOENT)
555		return nfserr_badowner;
556	if (ret)
557		return nfserrno(ret);
558	*id = item->id;
559	cache_put(&item->h, nn->nametoid_cache);
560	return 0;
561}
562
563static __be32 encode_ascii_id(struct xdr_stream *xdr, u32 id)
564{
565	char buf[11];
566	int len;
567	__be32 *p;
568
569	len = sprintf(buf, "%u", id);
570	p = xdr_reserve_space(xdr, len + 4);
571	if (!p)
572		return nfserr_resource;
573	p = xdr_encode_opaque(p, buf, len);
574	return 0;
575}
576
577static __be32 idmap_id_to_name(struct xdr_stream *xdr,
578			       struct svc_rqst *rqstp, int type, u32 id)
579{
580	struct ent *item, key = {
581		.id = id,
582		.type = type,
583	};
584	__be32 *p;
585	int ret;
586	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
587
588	strscpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
589	ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
590	if (ret == -ENOENT)
591		return encode_ascii_id(xdr, id);
592	if (ret)
593		return nfserrno(ret);
594	ret = strlen(item->name);
595	WARN_ON_ONCE(ret > IDMAP_NAMESZ);
596	p = xdr_reserve_space(xdr, ret + 4);
597	if (!p)
598		return nfserr_resource;
599	p = xdr_encode_opaque(p, item->name, ret);
600	cache_put(&item->h, nn->idtoname_cache);
601	return 0;
602}
603
604static bool
605numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
606{
607	int ret;
608	char buf[11];
609
610	if (namelen + 1 > sizeof(buf))
611		/* too long to represent a 32-bit id: */
612		return false;
613	/* Just to make sure it's null-terminated: */
614	memcpy(buf, name, namelen);
615	buf[namelen] = '\0';
616	ret = kstrtouint(buf, 10, id);
617	return ret == 0;
618}
619
620static __be32
621do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
622{
623	if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
624		if (numeric_name_to_id(rqstp, type, name, namelen, id))
625			return 0;
626		/*
627		 * otherwise, fall through and try idmapping, for
628		 * backwards compatibility with clients sending names:
629		 */
630	return idmap_name_to_id(rqstp, type, name, namelen, id);
631}
632
633static __be32 encode_name_from_id(struct xdr_stream *xdr,
634				  struct svc_rqst *rqstp, int type, u32 id)
635{
636	if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
637		return encode_ascii_id(xdr, id);
638	return idmap_id_to_name(xdr, rqstp, type, id);
639}
640
641__be32
642nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
643		kuid_t *uid)
644{
645	__be32 status;
646	u32 id = -1;
647
648	if (name == NULL || namelen == 0)
649		return nfserr_inval;
650
651	status = do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, &id);
652	*uid = make_kuid(nfsd_user_namespace(rqstp), id);
653	if (!uid_valid(*uid))
654		status = nfserr_badowner;
655	return status;
656}
657
658__be32
659nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
660		kgid_t *gid)
661{
662	__be32 status;
663	u32 id = -1;
664
665	if (name == NULL || namelen == 0)
666		return nfserr_inval;
667
668	status = do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, &id);
669	*gid = make_kgid(nfsd_user_namespace(rqstp), id);
670	if (!gid_valid(*gid))
671		status = nfserr_badowner;
672	return status;
673}
674
675__be32 nfsd4_encode_user(struct xdr_stream *xdr, struct svc_rqst *rqstp,
676			 kuid_t uid)
677{
678	u32 id = from_kuid_munged(nfsd_user_namespace(rqstp), uid);
679	return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_USER, id);
680}
681
682__be32 nfsd4_encode_group(struct xdr_stream *xdr, struct svc_rqst *rqstp,
683			  kgid_t gid)
684{
685	u32 id = from_kgid_munged(nfsd_user_namespace(rqstp), gid);
686	return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_GROUP, id);
687}