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1/*
2 * fs/nfs/idmap.c
3 *
4 * UID and GID to name mapping for clients.
5 *
6 * Copyright (c) 2002 The Regents of the University of Michigan.
7 * All rights reserved.
8 *
9 * Marius Aamodt Eriksen <marius@umich.edu>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 *
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its
21 * contributors may be used to endorse or promote products derived
22 * from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
31 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 */
36#include <linux/types.h>
37#include <linux/parser.h>
38#include <linux/fs.h>
39#include <net/net_namespace.h>
40#include <linux/sunrpc/rpc_pipe_fs.h>
41#include <linux/nfs_fs.h>
42#include <linux/nfs_fs_sb.h>
43#include <linux/key.h>
44#include <linux/keyctl.h>
45#include <linux/key-type.h>
46#include <keys/user-type.h>
47#include <linux/module.h>
48
49#include "internal.h"
50#include "netns.h"
51#include "nfs4idmap.h"
52#include "nfs4trace.h"
53
54#define NFS_UINT_MAXLEN 11
55
56static const struct cred *id_resolver_cache;
57static struct key_type key_type_id_resolver_legacy;
58
59struct idmap_legacy_upcalldata {
60 struct rpc_pipe_msg pipe_msg;
61 struct idmap_msg idmap_msg;
62 struct key_construction *key_cons;
63 struct idmap *idmap;
64};
65
66struct idmap {
67 struct rpc_pipe_dir_object idmap_pdo;
68 struct rpc_pipe *idmap_pipe;
69 struct idmap_legacy_upcalldata *idmap_upcall_data;
70 struct mutex idmap_mutex;
71};
72
73/**
74 * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
75 * @fattr: fully initialised struct nfs_fattr
76 * @owner_name: owner name string cache
77 * @group_name: group name string cache
78 */
79void nfs_fattr_init_names(struct nfs_fattr *fattr,
80 struct nfs4_string *owner_name,
81 struct nfs4_string *group_name)
82{
83 fattr->owner_name = owner_name;
84 fattr->group_name = group_name;
85}
86
87static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
88{
89 fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
90 kfree(fattr->owner_name->data);
91}
92
93static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
94{
95 fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
96 kfree(fattr->group_name->data);
97}
98
99static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
100{
101 struct nfs4_string *owner = fattr->owner_name;
102 kuid_t uid;
103
104 if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
105 return false;
106 if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
107 fattr->uid = uid;
108 fattr->valid |= NFS_ATTR_FATTR_OWNER;
109 }
110 return true;
111}
112
113static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
114{
115 struct nfs4_string *group = fattr->group_name;
116 kgid_t gid;
117
118 if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
119 return false;
120 if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
121 fattr->gid = gid;
122 fattr->valid |= NFS_ATTR_FATTR_GROUP;
123 }
124 return true;
125}
126
127/**
128 * nfs_fattr_free_names - free up the NFSv4 owner and group strings
129 * @fattr: a fully initialised nfs_fattr structure
130 */
131void nfs_fattr_free_names(struct nfs_fattr *fattr)
132{
133 if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
134 nfs_fattr_free_owner_name(fattr);
135 if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
136 nfs_fattr_free_group_name(fattr);
137}
138
139/**
140 * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
141 * @server: pointer to the filesystem nfs_server structure
142 * @fattr: a fully initialised nfs_fattr structure
143 *
144 * This helper maps the cached NFSv4 owner/group strings in fattr into
145 * their numeric uid/gid equivalents, and then frees the cached strings.
146 */
147void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
148{
149 if (nfs_fattr_map_owner_name(server, fattr))
150 nfs_fattr_free_owner_name(fattr);
151 if (nfs_fattr_map_group_name(server, fattr))
152 nfs_fattr_free_group_name(fattr);
153}
154
155int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
156{
157 unsigned long val;
158 char buf[16];
159
160 if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
161 return 0;
162 memcpy(buf, name, namelen);
163 buf[namelen] = '\0';
164 if (kstrtoul(buf, 0, &val) != 0)
165 return 0;
166 *res = val;
167 return 1;
168}
169EXPORT_SYMBOL_GPL(nfs_map_string_to_numeric);
170
171static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
172{
173 return snprintf(buf, buflen, "%u", id);
174}
175
176static struct key_type key_type_id_resolver = {
177 .name = "id_resolver",
178 .preparse = user_preparse,
179 .free_preparse = user_free_preparse,
180 .instantiate = generic_key_instantiate,
181 .revoke = user_revoke,
182 .destroy = user_destroy,
183 .describe = user_describe,
184 .read = user_read,
185};
186
187int nfs_idmap_init(void)
188{
189 struct cred *cred;
190 struct key *keyring;
191 int ret = 0;
192
193 printk(KERN_NOTICE "NFS: Registering the %s key type\n",
194 key_type_id_resolver.name);
195
196 cred = prepare_kernel_cred(NULL);
197 if (!cred)
198 return -ENOMEM;
199
200 keyring = keyring_alloc(".id_resolver",
201 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
202 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
203 KEY_USR_VIEW | KEY_USR_READ,
204 KEY_ALLOC_NOT_IN_QUOTA, NULL);
205 if (IS_ERR(keyring)) {
206 ret = PTR_ERR(keyring);
207 goto failed_put_cred;
208 }
209
210 ret = register_key_type(&key_type_id_resolver);
211 if (ret < 0)
212 goto failed_put_key;
213
214 ret = register_key_type(&key_type_id_resolver_legacy);
215 if (ret < 0)
216 goto failed_reg_legacy;
217
218 set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
219 cred->thread_keyring = keyring;
220 cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
221 id_resolver_cache = cred;
222 return 0;
223
224failed_reg_legacy:
225 unregister_key_type(&key_type_id_resolver);
226failed_put_key:
227 key_put(keyring);
228failed_put_cred:
229 put_cred(cred);
230 return ret;
231}
232
233void nfs_idmap_quit(void)
234{
235 key_revoke(id_resolver_cache->thread_keyring);
236 unregister_key_type(&key_type_id_resolver);
237 unregister_key_type(&key_type_id_resolver_legacy);
238 put_cred(id_resolver_cache);
239}
240
241/*
242 * Assemble the description to pass to request_key()
243 * This function will allocate a new string and update dest to point
244 * at it. The caller is responsible for freeing dest.
245 *
246 * On error 0 is returned. Otherwise, the length of dest is returned.
247 */
248static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
249 const char *type, size_t typelen, char **desc)
250{
251 char *cp;
252 size_t desclen = typelen + namelen + 2;
253
254 *desc = kmalloc(desclen, GFP_KERNEL);
255 if (!*desc)
256 return -ENOMEM;
257
258 cp = *desc;
259 memcpy(cp, type, typelen);
260 cp += typelen;
261 *cp++ = ':';
262
263 memcpy(cp, name, namelen);
264 cp += namelen;
265 *cp = '\0';
266 return desclen;
267}
268
269static struct key *nfs_idmap_request_key(const char *name, size_t namelen,
270 const char *type, struct idmap *idmap)
271{
272 char *desc;
273 struct key *rkey;
274 ssize_t ret;
275
276 ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
277 if (ret <= 0)
278 return ERR_PTR(ret);
279
280 rkey = request_key(&key_type_id_resolver, desc, "");
281 if (IS_ERR(rkey)) {
282 mutex_lock(&idmap->idmap_mutex);
283 rkey = request_key_with_auxdata(&key_type_id_resolver_legacy,
284 desc, "", 0, idmap);
285 mutex_unlock(&idmap->idmap_mutex);
286 }
287 if (!IS_ERR(rkey))
288 set_bit(KEY_FLAG_ROOT_CAN_INVAL, &rkey->flags);
289
290 kfree(desc);
291 return rkey;
292}
293
294static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
295 const char *type, void *data,
296 size_t data_size, struct idmap *idmap)
297{
298 const struct cred *saved_cred;
299 struct key *rkey;
300 const struct user_key_payload *payload;
301 ssize_t ret;
302
303 saved_cred = override_creds(id_resolver_cache);
304 rkey = nfs_idmap_request_key(name, namelen, type, idmap);
305 revert_creds(saved_cred);
306
307 if (IS_ERR(rkey)) {
308 ret = PTR_ERR(rkey);
309 goto out;
310 }
311
312 rcu_read_lock();
313 rkey->perm |= KEY_USR_VIEW;
314
315 ret = key_validate(rkey);
316 if (ret < 0)
317 goto out_up;
318
319 payload = user_key_payload(rkey);
320 if (IS_ERR_OR_NULL(payload)) {
321 ret = PTR_ERR(payload);
322 goto out_up;
323 }
324
325 ret = payload->datalen;
326 if (ret > 0 && ret <= data_size)
327 memcpy(data, payload->data, ret);
328 else
329 ret = -EINVAL;
330
331out_up:
332 rcu_read_unlock();
333 key_put(rkey);
334out:
335 return ret;
336}
337
338/* ID -> Name */
339static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
340 size_t buflen, struct idmap *idmap)
341{
342 char id_str[NFS_UINT_MAXLEN];
343 int id_len;
344 ssize_t ret;
345
346 id_len = snprintf(id_str, sizeof(id_str), "%u", id);
347 ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
348 if (ret < 0)
349 return -EINVAL;
350 return ret;
351}
352
353/* Name -> ID */
354static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
355 __u32 *id, struct idmap *idmap)
356{
357 char id_str[NFS_UINT_MAXLEN];
358 long id_long;
359 ssize_t data_size;
360 int ret = 0;
361
362 data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
363 if (data_size <= 0) {
364 ret = -EINVAL;
365 } else {
366 ret = kstrtol(id_str, 10, &id_long);
367 *id = (__u32)id_long;
368 }
369 return ret;
370}
371
372/* idmap classic begins here */
373
374enum {
375 Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
376};
377
378static const match_table_t nfs_idmap_tokens = {
379 { Opt_find_uid, "uid:%s" },
380 { Opt_find_gid, "gid:%s" },
381 { Opt_find_user, "user:%s" },
382 { Opt_find_group, "group:%s" },
383 { Opt_find_err, NULL }
384};
385
386static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *);
387static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
388 size_t);
389static void idmap_release_pipe(struct inode *);
390static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
391
392static const struct rpc_pipe_ops idmap_upcall_ops = {
393 .upcall = rpc_pipe_generic_upcall,
394 .downcall = idmap_pipe_downcall,
395 .release_pipe = idmap_release_pipe,
396 .destroy_msg = idmap_pipe_destroy_msg,
397};
398
399static struct key_type key_type_id_resolver_legacy = {
400 .name = "id_legacy",
401 .preparse = user_preparse,
402 .free_preparse = user_free_preparse,
403 .instantiate = generic_key_instantiate,
404 .revoke = user_revoke,
405 .destroy = user_destroy,
406 .describe = user_describe,
407 .read = user_read,
408 .request_key = nfs_idmap_legacy_upcall,
409};
410
411static void nfs_idmap_pipe_destroy(struct dentry *dir,
412 struct rpc_pipe_dir_object *pdo)
413{
414 struct idmap *idmap = pdo->pdo_data;
415 struct rpc_pipe *pipe = idmap->idmap_pipe;
416
417 if (pipe->dentry) {
418 rpc_unlink(pipe->dentry);
419 pipe->dentry = NULL;
420 }
421}
422
423static int nfs_idmap_pipe_create(struct dentry *dir,
424 struct rpc_pipe_dir_object *pdo)
425{
426 struct idmap *idmap = pdo->pdo_data;
427 struct rpc_pipe *pipe = idmap->idmap_pipe;
428 struct dentry *dentry;
429
430 dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
431 if (IS_ERR(dentry))
432 return PTR_ERR(dentry);
433 pipe->dentry = dentry;
434 return 0;
435}
436
437static const struct rpc_pipe_dir_object_ops nfs_idmap_pipe_dir_object_ops = {
438 .create = nfs_idmap_pipe_create,
439 .destroy = nfs_idmap_pipe_destroy,
440};
441
442int
443nfs_idmap_new(struct nfs_client *clp)
444{
445 struct idmap *idmap;
446 struct rpc_pipe *pipe;
447 int error;
448
449 idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
450 if (idmap == NULL)
451 return -ENOMEM;
452
453 rpc_init_pipe_dir_object(&idmap->idmap_pdo,
454 &nfs_idmap_pipe_dir_object_ops,
455 idmap);
456
457 pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
458 if (IS_ERR(pipe)) {
459 error = PTR_ERR(pipe);
460 goto err;
461 }
462 idmap->idmap_pipe = pipe;
463 mutex_init(&idmap->idmap_mutex);
464
465 error = rpc_add_pipe_dir_object(clp->cl_net,
466 &clp->cl_rpcclient->cl_pipedir_objects,
467 &idmap->idmap_pdo);
468 if (error)
469 goto err_destroy_pipe;
470
471 clp->cl_idmap = idmap;
472 return 0;
473err_destroy_pipe:
474 rpc_destroy_pipe_data(idmap->idmap_pipe);
475err:
476 kfree(idmap);
477 return error;
478}
479
480void
481nfs_idmap_delete(struct nfs_client *clp)
482{
483 struct idmap *idmap = clp->cl_idmap;
484
485 if (!idmap)
486 return;
487 clp->cl_idmap = NULL;
488 rpc_remove_pipe_dir_object(clp->cl_net,
489 &clp->cl_rpcclient->cl_pipedir_objects,
490 &idmap->idmap_pdo);
491 rpc_destroy_pipe_data(idmap->idmap_pipe);
492 kfree(idmap);
493}
494
495static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
496 struct idmap_msg *im,
497 struct rpc_pipe_msg *msg)
498{
499 substring_t substr;
500 int token, ret;
501
502 im->im_type = IDMAP_TYPE_GROUP;
503 token = match_token(desc, nfs_idmap_tokens, &substr);
504
505 switch (token) {
506 case Opt_find_uid:
507 im->im_type = IDMAP_TYPE_USER;
508 case Opt_find_gid:
509 im->im_conv = IDMAP_CONV_NAMETOID;
510 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
511 break;
512
513 case Opt_find_user:
514 im->im_type = IDMAP_TYPE_USER;
515 case Opt_find_group:
516 im->im_conv = IDMAP_CONV_IDTONAME;
517 ret = match_int(&substr, &im->im_id);
518 break;
519
520 default:
521 ret = -EINVAL;
522 goto out;
523 }
524
525 msg->data = im;
526 msg->len = sizeof(struct idmap_msg);
527
528out:
529 return ret;
530}
531
532static bool
533nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
534 struct idmap_legacy_upcalldata *data)
535{
536 if (idmap->idmap_upcall_data != NULL) {
537 WARN_ON_ONCE(1);
538 return false;
539 }
540 idmap->idmap_upcall_data = data;
541 return true;
542}
543
544static void
545nfs_idmap_complete_pipe_upcall_locked(struct idmap *idmap, int ret)
546{
547 struct key_construction *cons = idmap->idmap_upcall_data->key_cons;
548
549 kfree(idmap->idmap_upcall_data);
550 idmap->idmap_upcall_data = NULL;
551 complete_request_key(cons, ret);
552}
553
554static void
555nfs_idmap_abort_pipe_upcall(struct idmap *idmap, int ret)
556{
557 if (idmap->idmap_upcall_data != NULL)
558 nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
559}
560
561static int nfs_idmap_legacy_upcall(struct key_construction *cons,
562 const char *op,
563 void *aux)
564{
565 struct idmap_legacy_upcalldata *data;
566 struct rpc_pipe_msg *msg;
567 struct idmap_msg *im;
568 struct idmap *idmap = (struct idmap *)aux;
569 struct key *key = cons->key;
570 int ret = -ENOMEM;
571
572 /* msg and im are freed in idmap_pipe_destroy_msg */
573 data = kzalloc(sizeof(*data), GFP_KERNEL);
574 if (!data)
575 goto out1;
576
577 msg = &data->pipe_msg;
578 im = &data->idmap_msg;
579 data->idmap = idmap;
580 data->key_cons = cons;
581
582 ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
583 if (ret < 0)
584 goto out2;
585
586 ret = -EAGAIN;
587 if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
588 goto out2;
589
590 ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
591 if (ret < 0)
592 nfs_idmap_abort_pipe_upcall(idmap, ret);
593
594 return ret;
595out2:
596 kfree(data);
597out1:
598 complete_request_key(cons, ret);
599 return ret;
600}
601
602static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
603{
604 return key_instantiate_and_link(key, data, datalen,
605 id_resolver_cache->thread_keyring,
606 authkey);
607}
608
609static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
610 struct idmap_msg *upcall,
611 struct key *key, struct key *authkey)
612{
613 char id_str[NFS_UINT_MAXLEN];
614 size_t len;
615 int ret = -ENOKEY;
616
617 /* ret = -ENOKEY */
618 if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
619 goto out;
620 switch (im->im_conv) {
621 case IDMAP_CONV_NAMETOID:
622 if (strcmp(upcall->im_name, im->im_name) != 0)
623 break;
624 /* Note: here we store the NUL terminator too */
625 len = sprintf(id_str, "%d", im->im_id) + 1;
626 ret = nfs_idmap_instantiate(key, authkey, id_str, len);
627 break;
628 case IDMAP_CONV_IDTONAME:
629 if (upcall->im_id != im->im_id)
630 break;
631 len = strlen(im->im_name);
632 ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
633 break;
634 default:
635 ret = -EINVAL;
636 }
637out:
638 return ret;
639}
640
641static ssize_t
642idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
643{
644 struct rpc_inode *rpci = RPC_I(file_inode(filp));
645 struct idmap *idmap = (struct idmap *)rpci->private;
646 struct key_construction *cons;
647 struct idmap_msg im;
648 size_t namelen_in;
649 int ret = -ENOKEY;
650
651 /* If instantiation is successful, anyone waiting for key construction
652 * will have been woken up and someone else may now have used
653 * idmap_key_cons - so after this point we may no longer touch it.
654 */
655 if (idmap->idmap_upcall_data == NULL)
656 goto out_noupcall;
657
658 cons = idmap->idmap_upcall_data->key_cons;
659
660 if (mlen != sizeof(im)) {
661 ret = -ENOSPC;
662 goto out;
663 }
664
665 if (copy_from_user(&im, src, mlen) != 0) {
666 ret = -EFAULT;
667 goto out;
668 }
669
670 if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
671 ret = -ENOKEY;
672 goto out;
673 }
674
675 namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
676 if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
677 ret = -EINVAL;
678 goto out;
679}
680
681 ret = nfs_idmap_read_and_verify_message(&im,
682 &idmap->idmap_upcall_data->idmap_msg,
683 cons->key, cons->authkey);
684 if (ret >= 0) {
685 key_set_timeout(cons->key, nfs_idmap_cache_timeout);
686 ret = mlen;
687 }
688
689out:
690 nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
691out_noupcall:
692 return ret;
693}
694
695static void
696idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
697{
698 struct idmap_legacy_upcalldata *data = container_of(msg,
699 struct idmap_legacy_upcalldata,
700 pipe_msg);
701 struct idmap *idmap = data->idmap;
702
703 if (msg->errno)
704 nfs_idmap_abort_pipe_upcall(idmap, msg->errno);
705}
706
707static void
708idmap_release_pipe(struct inode *inode)
709{
710 struct rpc_inode *rpci = RPC_I(inode);
711 struct idmap *idmap = (struct idmap *)rpci->private;
712
713 nfs_idmap_abort_pipe_upcall(idmap, -EPIPE);
714}
715
716int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
717{
718 struct idmap *idmap = server->nfs_client->cl_idmap;
719 __u32 id = -1;
720 int ret = 0;
721
722 if (!nfs_map_string_to_numeric(name, namelen, &id))
723 ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
724 if (ret == 0) {
725 *uid = make_kuid(&init_user_ns, id);
726 if (!uid_valid(*uid))
727 ret = -ERANGE;
728 }
729 trace_nfs4_map_name_to_uid(name, namelen, id, ret);
730 return ret;
731}
732
733int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
734{
735 struct idmap *idmap = server->nfs_client->cl_idmap;
736 __u32 id = -1;
737 int ret = 0;
738
739 if (!nfs_map_string_to_numeric(name, namelen, &id))
740 ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
741 if (ret == 0) {
742 *gid = make_kgid(&init_user_ns, id);
743 if (!gid_valid(*gid))
744 ret = -ERANGE;
745 }
746 trace_nfs4_map_group_to_gid(name, namelen, id, ret);
747 return ret;
748}
749
750int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
751{
752 struct idmap *idmap = server->nfs_client->cl_idmap;
753 int ret = -EINVAL;
754 __u32 id;
755
756 id = from_kuid(&init_user_ns, uid);
757 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
758 ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
759 if (ret < 0)
760 ret = nfs_map_numeric_to_string(id, buf, buflen);
761 trace_nfs4_map_uid_to_name(buf, ret, id, ret);
762 return ret;
763}
764int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
765{
766 struct idmap *idmap = server->nfs_client->cl_idmap;
767 int ret = -EINVAL;
768 __u32 id;
769
770 id = from_kgid(&init_user_ns, gid);
771 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
772 ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
773 if (ret < 0)
774 ret = nfs_map_numeric_to_string(id, buf, buflen);
775 trace_nfs4_map_gid_to_group(buf, ret, id, ret);
776 return ret;
777}
1/*
2 * fs/nfs/idmap.c
3 *
4 * UID and GID to name mapping for clients.
5 *
6 * Copyright (c) 2002 The Regents of the University of Michigan.
7 * All rights reserved.
8 *
9 * Marius Aamodt Eriksen <marius@umich.edu>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 *
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its
21 * contributors may be used to endorse or promote products derived
22 * from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
31 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 */
36#include <linux/types.h>
37#include <linux/parser.h>
38#include <linux/fs.h>
39#include <net/net_namespace.h>
40#include <linux/sunrpc/rpc_pipe_fs.h>
41#include <linux/nfs_fs.h>
42#include <linux/nfs_fs_sb.h>
43#include <linux/key.h>
44#include <linux/keyctl.h>
45#include <linux/key-type.h>
46#include <keys/user-type.h>
47#include <keys/request_key_auth-type.h>
48#include <linux/module.h>
49#include <linux/user_namespace.h>
50
51#include "internal.h"
52#include "netns.h"
53#include "nfs4idmap.h"
54#include "nfs4trace.h"
55
56#define NFS_UINT_MAXLEN 11
57
58static const struct cred *id_resolver_cache;
59static struct key_type key_type_id_resolver_legacy;
60
61struct idmap_legacy_upcalldata {
62 struct rpc_pipe_msg pipe_msg;
63 struct idmap_msg idmap_msg;
64 struct key *authkey;
65 struct idmap *idmap;
66};
67
68struct idmap {
69 struct rpc_pipe_dir_object idmap_pdo;
70 struct rpc_pipe *idmap_pipe;
71 struct idmap_legacy_upcalldata *idmap_upcall_data;
72 struct mutex idmap_mutex;
73 struct user_namespace *user_ns;
74};
75
76static struct user_namespace *idmap_userns(const struct idmap *idmap)
77{
78 if (idmap && idmap->user_ns)
79 return idmap->user_ns;
80 return &init_user_ns;
81}
82
83/**
84 * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
85 * @fattr: fully initialised struct nfs_fattr
86 * @owner_name: owner name string cache
87 * @group_name: group name string cache
88 */
89void nfs_fattr_init_names(struct nfs_fattr *fattr,
90 struct nfs4_string *owner_name,
91 struct nfs4_string *group_name)
92{
93 fattr->owner_name = owner_name;
94 fattr->group_name = group_name;
95}
96
97static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
98{
99 fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
100 kfree(fattr->owner_name->data);
101}
102
103static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
104{
105 fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
106 kfree(fattr->group_name->data);
107}
108
109static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
110{
111 struct nfs4_string *owner = fattr->owner_name;
112 kuid_t uid;
113
114 if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
115 return false;
116 if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
117 fattr->uid = uid;
118 fattr->valid |= NFS_ATTR_FATTR_OWNER;
119 }
120 return true;
121}
122
123static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
124{
125 struct nfs4_string *group = fattr->group_name;
126 kgid_t gid;
127
128 if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
129 return false;
130 if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
131 fattr->gid = gid;
132 fattr->valid |= NFS_ATTR_FATTR_GROUP;
133 }
134 return true;
135}
136
137/**
138 * nfs_fattr_free_names - free up the NFSv4 owner and group strings
139 * @fattr: a fully initialised nfs_fattr structure
140 */
141void nfs_fattr_free_names(struct nfs_fattr *fattr)
142{
143 if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
144 nfs_fattr_free_owner_name(fattr);
145 if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
146 nfs_fattr_free_group_name(fattr);
147}
148
149/**
150 * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
151 * @server: pointer to the filesystem nfs_server structure
152 * @fattr: a fully initialised nfs_fattr structure
153 *
154 * This helper maps the cached NFSv4 owner/group strings in fattr into
155 * their numeric uid/gid equivalents, and then frees the cached strings.
156 */
157void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
158{
159 if (nfs_fattr_map_owner_name(server, fattr))
160 nfs_fattr_free_owner_name(fattr);
161 if (nfs_fattr_map_group_name(server, fattr))
162 nfs_fattr_free_group_name(fattr);
163}
164
165int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
166{
167 unsigned long val;
168 char buf[16];
169
170 if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
171 return 0;
172 memcpy(buf, name, namelen);
173 buf[namelen] = '\0';
174 if (kstrtoul(buf, 0, &val) != 0)
175 return 0;
176 *res = val;
177 return 1;
178}
179EXPORT_SYMBOL_GPL(nfs_map_string_to_numeric);
180
181static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
182{
183 return snprintf(buf, buflen, "%u", id);
184}
185
186static struct key_type key_type_id_resolver = {
187 .name = "id_resolver",
188 .preparse = user_preparse,
189 .free_preparse = user_free_preparse,
190 .instantiate = generic_key_instantiate,
191 .revoke = user_revoke,
192 .destroy = user_destroy,
193 .describe = user_describe,
194 .read = user_read,
195};
196
197int nfs_idmap_init(void)
198{
199 struct cred *cred;
200 struct key *keyring;
201 int ret = 0;
202
203 printk(KERN_NOTICE "NFS: Registering the %s key type\n",
204 key_type_id_resolver.name);
205
206 cred = prepare_kernel_cred(&init_task);
207 if (!cred)
208 return -ENOMEM;
209
210 keyring = keyring_alloc(".id_resolver",
211 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
212 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
213 KEY_USR_VIEW | KEY_USR_READ,
214 KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
215 if (IS_ERR(keyring)) {
216 ret = PTR_ERR(keyring);
217 goto failed_put_cred;
218 }
219
220 ret = register_key_type(&key_type_id_resolver);
221 if (ret < 0)
222 goto failed_put_key;
223
224 ret = register_key_type(&key_type_id_resolver_legacy);
225 if (ret < 0)
226 goto failed_reg_legacy;
227
228 set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
229 cred->thread_keyring = keyring;
230 cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
231 id_resolver_cache = cred;
232 return 0;
233
234failed_reg_legacy:
235 unregister_key_type(&key_type_id_resolver);
236failed_put_key:
237 key_put(keyring);
238failed_put_cred:
239 put_cred(cred);
240 return ret;
241}
242
243void nfs_idmap_quit(void)
244{
245 key_revoke(id_resolver_cache->thread_keyring);
246 unregister_key_type(&key_type_id_resolver);
247 unregister_key_type(&key_type_id_resolver_legacy);
248 put_cred(id_resolver_cache);
249}
250
251/*
252 * Assemble the description to pass to request_key()
253 * This function will allocate a new string and update dest to point
254 * at it. The caller is responsible for freeing dest.
255 *
256 * On error 0 is returned. Otherwise, the length of dest is returned.
257 */
258static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
259 const char *type, size_t typelen, char **desc)
260{
261 char *cp;
262 size_t desclen = typelen + namelen + 2;
263
264 *desc = kmalloc(desclen, GFP_KERNEL);
265 if (!*desc)
266 return -ENOMEM;
267
268 cp = *desc;
269 memcpy(cp, type, typelen);
270 cp += typelen;
271 *cp++ = ':';
272
273 memcpy(cp, name, namelen);
274 cp += namelen;
275 *cp = '\0';
276 return desclen;
277}
278
279static struct key *nfs_idmap_request_key(const char *name, size_t namelen,
280 const char *type, struct idmap *idmap)
281{
282 char *desc;
283 struct key *rkey = ERR_PTR(-EAGAIN);
284 ssize_t ret;
285
286 ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
287 if (ret < 0)
288 return ERR_PTR(ret);
289
290 if (!idmap->user_ns || idmap->user_ns == &init_user_ns)
291 rkey = request_key(&key_type_id_resolver, desc, "");
292 if (IS_ERR(rkey)) {
293 mutex_lock(&idmap->idmap_mutex);
294 rkey = request_key_with_auxdata(&key_type_id_resolver_legacy,
295 desc, NULL, "", 0, idmap);
296 mutex_unlock(&idmap->idmap_mutex);
297 }
298 if (!IS_ERR(rkey))
299 set_bit(KEY_FLAG_ROOT_CAN_INVAL, &rkey->flags);
300
301 kfree(desc);
302 return rkey;
303}
304
305static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
306 const char *type, void *data,
307 size_t data_size, struct idmap *idmap)
308{
309 const struct cred *saved_cred;
310 struct key *rkey;
311 const struct user_key_payload *payload;
312 ssize_t ret;
313
314 saved_cred = override_creds(id_resolver_cache);
315 rkey = nfs_idmap_request_key(name, namelen, type, idmap);
316 revert_creds(saved_cred);
317
318 if (IS_ERR(rkey)) {
319 ret = PTR_ERR(rkey);
320 goto out;
321 }
322
323 rcu_read_lock();
324 rkey->perm |= KEY_USR_VIEW;
325
326 ret = key_validate(rkey);
327 if (ret < 0)
328 goto out_up;
329
330 payload = user_key_payload_rcu(rkey);
331 if (IS_ERR_OR_NULL(payload)) {
332 ret = PTR_ERR(payload);
333 goto out_up;
334 }
335
336 ret = payload->datalen;
337 if (ret > 0 && ret <= data_size)
338 memcpy(data, payload->data, ret);
339 else
340 ret = -EINVAL;
341
342out_up:
343 rcu_read_unlock();
344 key_put(rkey);
345out:
346 return ret;
347}
348
349/* ID -> Name */
350static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
351 size_t buflen, struct idmap *idmap)
352{
353 char id_str[NFS_UINT_MAXLEN];
354 int id_len;
355 ssize_t ret;
356
357 id_len = nfs_map_numeric_to_string(id, id_str, sizeof(id_str));
358 ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
359 if (ret < 0)
360 return -EINVAL;
361 return ret;
362}
363
364/* Name -> ID */
365static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
366 __u32 *id, struct idmap *idmap)
367{
368 char id_str[NFS_UINT_MAXLEN];
369 long id_long;
370 ssize_t data_size;
371 int ret = 0;
372
373 data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
374 if (data_size <= 0) {
375 ret = -EINVAL;
376 } else {
377 ret = kstrtol(id_str, 10, &id_long);
378 if (!ret)
379 *id = (__u32)id_long;
380 }
381 return ret;
382}
383
384/* idmap classic begins here */
385
386enum {
387 Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
388};
389
390static const match_table_t nfs_idmap_tokens = {
391 { Opt_find_uid, "uid:%s" },
392 { Opt_find_gid, "gid:%s" },
393 { Opt_find_user, "user:%s" },
394 { Opt_find_group, "group:%s" },
395 { Opt_find_err, NULL }
396};
397
398static int nfs_idmap_legacy_upcall(struct key *, void *);
399static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
400 size_t);
401static void idmap_release_pipe(struct inode *);
402static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
403
404static const struct rpc_pipe_ops idmap_upcall_ops = {
405 .upcall = rpc_pipe_generic_upcall,
406 .downcall = idmap_pipe_downcall,
407 .release_pipe = idmap_release_pipe,
408 .destroy_msg = idmap_pipe_destroy_msg,
409};
410
411static struct key_type key_type_id_resolver_legacy = {
412 .name = "id_legacy",
413 .preparse = user_preparse,
414 .free_preparse = user_free_preparse,
415 .instantiate = generic_key_instantiate,
416 .revoke = user_revoke,
417 .destroy = user_destroy,
418 .describe = user_describe,
419 .read = user_read,
420 .request_key = nfs_idmap_legacy_upcall,
421};
422
423static void nfs_idmap_pipe_destroy(struct dentry *dir,
424 struct rpc_pipe_dir_object *pdo)
425{
426 struct idmap *idmap = pdo->pdo_data;
427 struct rpc_pipe *pipe = idmap->idmap_pipe;
428
429 if (pipe->dentry) {
430 rpc_unlink(pipe->dentry);
431 pipe->dentry = NULL;
432 }
433}
434
435static int nfs_idmap_pipe_create(struct dentry *dir,
436 struct rpc_pipe_dir_object *pdo)
437{
438 struct idmap *idmap = pdo->pdo_data;
439 struct rpc_pipe *pipe = idmap->idmap_pipe;
440 struct dentry *dentry;
441
442 dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
443 if (IS_ERR(dentry))
444 return PTR_ERR(dentry);
445 pipe->dentry = dentry;
446 return 0;
447}
448
449static const struct rpc_pipe_dir_object_ops nfs_idmap_pipe_dir_object_ops = {
450 .create = nfs_idmap_pipe_create,
451 .destroy = nfs_idmap_pipe_destroy,
452};
453
454int
455nfs_idmap_new(struct nfs_client *clp)
456{
457 struct idmap *idmap;
458 struct rpc_pipe *pipe;
459 int error;
460
461 idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
462 if (idmap == NULL)
463 return -ENOMEM;
464
465 mutex_init(&idmap->idmap_mutex);
466 idmap->user_ns = get_user_ns(clp->cl_rpcclient->cl_cred->user_ns);
467
468 rpc_init_pipe_dir_object(&idmap->idmap_pdo,
469 &nfs_idmap_pipe_dir_object_ops,
470 idmap);
471
472 pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
473 if (IS_ERR(pipe)) {
474 error = PTR_ERR(pipe);
475 goto err;
476 }
477 idmap->idmap_pipe = pipe;
478
479 error = rpc_add_pipe_dir_object(clp->cl_net,
480 &clp->cl_rpcclient->cl_pipedir_objects,
481 &idmap->idmap_pdo);
482 if (error)
483 goto err_destroy_pipe;
484
485 clp->cl_idmap = idmap;
486 return 0;
487err_destroy_pipe:
488 rpc_destroy_pipe_data(idmap->idmap_pipe);
489err:
490 put_user_ns(idmap->user_ns);
491 kfree(idmap);
492 return error;
493}
494
495void
496nfs_idmap_delete(struct nfs_client *clp)
497{
498 struct idmap *idmap = clp->cl_idmap;
499
500 if (!idmap)
501 return;
502 clp->cl_idmap = NULL;
503 rpc_remove_pipe_dir_object(clp->cl_net,
504 &clp->cl_rpcclient->cl_pipedir_objects,
505 &idmap->idmap_pdo);
506 rpc_destroy_pipe_data(idmap->idmap_pipe);
507 put_user_ns(idmap->user_ns);
508 kfree(idmap);
509}
510
511static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
512 struct idmap_msg *im,
513 struct rpc_pipe_msg *msg)
514{
515 substring_t substr;
516 int token, ret;
517
518 im->im_type = IDMAP_TYPE_GROUP;
519 token = match_token(desc, nfs_idmap_tokens, &substr);
520
521 switch (token) {
522 case Opt_find_uid:
523 im->im_type = IDMAP_TYPE_USER;
524 fallthrough;
525 case Opt_find_gid:
526 im->im_conv = IDMAP_CONV_NAMETOID;
527 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
528 break;
529
530 case Opt_find_user:
531 im->im_type = IDMAP_TYPE_USER;
532 fallthrough;
533 case Opt_find_group:
534 im->im_conv = IDMAP_CONV_IDTONAME;
535 ret = match_int(&substr, &im->im_id);
536 if (ret)
537 goto out;
538 break;
539
540 default:
541 ret = -EINVAL;
542 goto out;
543 }
544
545 msg->data = im;
546 msg->len = sizeof(struct idmap_msg);
547
548out:
549 return ret;
550}
551
552static bool
553nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
554 struct idmap_legacy_upcalldata *data)
555{
556 if (idmap->idmap_upcall_data != NULL) {
557 WARN_ON_ONCE(1);
558 return false;
559 }
560 idmap->idmap_upcall_data = data;
561 return true;
562}
563
564static void nfs_idmap_complete_pipe_upcall(struct idmap_legacy_upcalldata *data,
565 int ret)
566{
567 complete_request_key(data->authkey, ret);
568 key_put(data->authkey);
569 kfree(data);
570}
571
572static void nfs_idmap_abort_pipe_upcall(struct idmap *idmap,
573 struct idmap_legacy_upcalldata *data,
574 int ret)
575{
576 if (cmpxchg(&idmap->idmap_upcall_data, data, NULL) == data)
577 nfs_idmap_complete_pipe_upcall(data, ret);
578}
579
580static int nfs_idmap_legacy_upcall(struct key *authkey, void *aux)
581{
582 struct idmap_legacy_upcalldata *data;
583 struct request_key_auth *rka = get_request_key_auth(authkey);
584 struct rpc_pipe_msg *msg;
585 struct idmap_msg *im;
586 struct idmap *idmap = aux;
587 struct key *key = rka->target_key;
588 int ret = -ENOKEY;
589
590 if (!aux)
591 goto out1;
592
593 /* msg and im are freed in idmap_pipe_destroy_msg */
594 ret = -ENOMEM;
595 data = kzalloc(sizeof(*data), GFP_KERNEL);
596 if (!data)
597 goto out1;
598
599 msg = &data->pipe_msg;
600 im = &data->idmap_msg;
601 data->idmap = idmap;
602 data->authkey = key_get(authkey);
603
604 ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
605 if (ret < 0)
606 goto out2;
607
608 ret = -EAGAIN;
609 if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
610 goto out2;
611
612 ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
613 if (ret < 0)
614 nfs_idmap_abort_pipe_upcall(idmap, data, ret);
615
616 return ret;
617out2:
618 kfree(data);
619out1:
620 complete_request_key(authkey, ret);
621 return ret;
622}
623
624static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
625{
626 return key_instantiate_and_link(key, data, datalen,
627 id_resolver_cache->thread_keyring,
628 authkey);
629}
630
631static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
632 struct idmap_msg *upcall,
633 struct key *key, struct key *authkey)
634{
635 char id_str[NFS_UINT_MAXLEN];
636 size_t len;
637 int ret = -ENOKEY;
638
639 /* ret = -ENOKEY */
640 if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
641 goto out;
642 switch (im->im_conv) {
643 case IDMAP_CONV_NAMETOID:
644 if (strcmp(upcall->im_name, im->im_name) != 0)
645 break;
646 /* Note: here we store the NUL terminator too */
647 len = 1 + nfs_map_numeric_to_string(im->im_id, id_str,
648 sizeof(id_str));
649 ret = nfs_idmap_instantiate(key, authkey, id_str, len);
650 break;
651 case IDMAP_CONV_IDTONAME:
652 if (upcall->im_id != im->im_id)
653 break;
654 len = strlen(im->im_name);
655 ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
656 break;
657 default:
658 ret = -EINVAL;
659 }
660out:
661 return ret;
662}
663
664static ssize_t
665idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
666{
667 struct request_key_auth *rka;
668 struct rpc_inode *rpci = RPC_I(file_inode(filp));
669 struct idmap *idmap = (struct idmap *)rpci->private;
670 struct idmap_legacy_upcalldata *data;
671 struct key *authkey;
672 struct idmap_msg im;
673 size_t namelen_in;
674 int ret = -ENOKEY;
675
676 /* If instantiation is successful, anyone waiting for key construction
677 * will have been woken up and someone else may now have used
678 * idmap_key_cons - so after this point we may no longer touch it.
679 */
680 data = xchg(&idmap->idmap_upcall_data, NULL);
681 if (data == NULL)
682 goto out_noupcall;
683
684 authkey = data->authkey;
685 rka = get_request_key_auth(authkey);
686
687 if (mlen != sizeof(im)) {
688 ret = -ENOSPC;
689 goto out;
690 }
691
692 if (copy_from_user(&im, src, mlen) != 0) {
693 ret = -EFAULT;
694 goto out;
695 }
696
697 if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
698 ret = -ENOKEY;
699 goto out;
700 }
701
702 namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
703 if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
704 ret = -EINVAL;
705 goto out;
706 }
707
708 ret = nfs_idmap_read_and_verify_message(&im, &data->idmap_msg,
709 rka->target_key, authkey);
710 if (ret >= 0) {
711 key_set_timeout(rka->target_key, nfs_idmap_cache_timeout);
712 ret = mlen;
713 }
714
715out:
716 nfs_idmap_complete_pipe_upcall(data, ret);
717out_noupcall:
718 return ret;
719}
720
721static void
722idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
723{
724 struct idmap_legacy_upcalldata *data = container_of(msg,
725 struct idmap_legacy_upcalldata,
726 pipe_msg);
727 struct idmap *idmap = data->idmap;
728
729 if (msg->errno)
730 nfs_idmap_abort_pipe_upcall(idmap, data, msg->errno);
731}
732
733static void
734idmap_release_pipe(struct inode *inode)
735{
736 struct rpc_inode *rpci = RPC_I(inode);
737 struct idmap *idmap = (struct idmap *)rpci->private;
738 struct idmap_legacy_upcalldata *data;
739
740 data = xchg(&idmap->idmap_upcall_data, NULL);
741 if (data)
742 nfs_idmap_complete_pipe_upcall(data, -EPIPE);
743}
744
745int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
746{
747 struct idmap *idmap = server->nfs_client->cl_idmap;
748 __u32 id = -1;
749 int ret = 0;
750
751 if (!nfs_map_string_to_numeric(name, namelen, &id))
752 ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
753 if (ret == 0) {
754 *uid = make_kuid(idmap_userns(idmap), id);
755 if (!uid_valid(*uid))
756 ret = -ERANGE;
757 }
758 trace_nfs4_map_name_to_uid(name, namelen, id, ret);
759 return ret;
760}
761
762int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
763{
764 struct idmap *idmap = server->nfs_client->cl_idmap;
765 __u32 id = -1;
766 int ret = 0;
767
768 if (!nfs_map_string_to_numeric(name, namelen, &id))
769 ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
770 if (ret == 0) {
771 *gid = make_kgid(idmap_userns(idmap), id);
772 if (!gid_valid(*gid))
773 ret = -ERANGE;
774 }
775 trace_nfs4_map_group_to_gid(name, namelen, id, ret);
776 return ret;
777}
778
779int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
780{
781 struct idmap *idmap = server->nfs_client->cl_idmap;
782 int ret = -EINVAL;
783 __u32 id;
784
785 id = from_kuid_munged(idmap_userns(idmap), uid);
786 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
787 ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
788 if (ret < 0)
789 ret = nfs_map_numeric_to_string(id, buf, buflen);
790 trace_nfs4_map_uid_to_name(buf, ret, id, ret);
791 return ret;
792}
793int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
794{
795 struct idmap *idmap = server->nfs_client->cl_idmap;
796 int ret = -EINVAL;
797 __u32 id;
798
799 id = from_kgid_munged(idmap_userns(idmap), gid);
800 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
801 ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
802 if (ret < 0)
803 ret = nfs_map_numeric_to_string(id, buf, buflen);
804 trace_nfs4_map_gid_to_group(buf, ret, id, ret);
805 return ret;
806}