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(objp: 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(objp: 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(p: name, c: '@', size: namelen) != NULL || namelen >= sizeof(buf))
171 return 0;
172 memcpy(buf, name, namelen);
173 buf[namelen] = '\0';
174 if (kstrtoul(s: buf, base: 0, res: &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, size: buflen, fmt: "%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(description: ".id_resolver",
211 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
212 perm: (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(key: id_resolver_cache->thread_keyring);
246 unregister_key_type(ktype: &key_type_id_resolver);
247 unregister_key_type(ktype: &key_type_id_resolver_legacy);
248 put_cred(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(size: 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(error: -EAGAIN);
284 ssize_t ret;
285
286 ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), desc: &desc);
287 if (ret < 0)
288 return ERR_PTR(error: ret);
289
290 if (!idmap->user_ns || idmap->user_ns == &init_user_ns)
291 rkey = request_key(type: &key_type_id_resolver, description: desc, callout_info: "");
292 if (IS_ERR(ptr: rkey)) {
293 mutex_lock(&idmap->idmap_mutex);
294 rkey = request_key_with_auxdata(type: &key_type_id_resolver_legacy,
295 description: desc, NULL, callout_info: "", callout_len: 0, aux: idmap);
296 mutex_unlock(lock: &idmap->idmap_mutex);
297 }
298 if (!IS_ERR(ptr: rkey))
299 set_bit(KEY_FLAG_ROOT_CAN_INVAL, addr: &rkey->flags);
300
301 kfree(objp: 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(ptr: rkey)) {
319 ret = PTR_ERR(ptr: rkey);
320 goto out;
321 }
322
323 rcu_read_lock();
324 rkey->perm |= KEY_USR_VIEW;
325
326 ret = key_validate(key: rkey);
327 if (ret < 0)
328 goto out_up;
329
330 payload = user_key_payload_rcu(key: rkey);
331 if (IS_ERR_OR_NULL(ptr: payload)) {
332 ret = PTR_ERR(ptr: 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(key: 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, buf: id_str, buflen: sizeof(id_str));
358 ret = nfs_idmap_get_key(name: id_str, namelen: id_len, type, data: buf, data_size: 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, data: id_str, NFS_UINT_MAXLEN, idmap);
374 if (data_size <= 0) {
375 ret = -EINVAL;
376 } else {
377 ret = kstrtol(s: id_str, base: 10, res: &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(ptr: dentry))
444 return PTR_ERR(ptr: 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(size: 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(ns: clp->cl_rpcclient->cl_cred->user_ns);
467
468 rpc_init_pipe_dir_object(pdo: &idmap->idmap_pdo,
469 pdo_ops: &nfs_idmap_pipe_dir_object_ops,
470 pdo_data: idmap);
471
472 pipe = rpc_mkpipe_data(ops: &idmap_upcall_ops, flags: 0);
473 if (IS_ERR(ptr: pipe)) {
474 error = PTR_ERR(ptr: pipe);
475 goto err;
476 }
477 idmap->idmap_pipe = pipe;
478
479 error = rpc_add_pipe_dir_object(net: clp->cl_net,
480 pdh: &clp->cl_rpcclient->cl_pipedir_objects,
481 pdo: &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(pipe: idmap->idmap_pipe);
489err:
490 put_user_ns(ns: idmap->user_ns);
491 kfree(objp: 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(net: clp->cl_net,
504 pdh: &clp->cl_rpcclient->cl_pipedir_objects,
505 pdo: &idmap->idmap_pdo);
506 rpc_destroy_pipe_data(pipe: idmap->idmap_pipe);
507 put_user_ns(ns: idmap->user_ns);
508 kfree(objp: 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, table: nfs_idmap_tokens, args: &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, result: &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(authkey: data->authkey, error: ret);
568 key_put(key: data->authkey);
569 kfree(objp: 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(key: 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(size: 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(key: authkey);
603
604 ret = nfs_idmap_prepare_message(desc: 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(objp: data);
619out1:
620 complete_request_key(authkey, error: 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 keyring: 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(id: im->im_id, buf: id_str,
648 buflen: sizeof(id_str));
649 ret = nfs_idmap_instantiate(key, authkey, data: id_str, datalen: 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, data: im->im_name, datalen: 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(inode: file_inode(f: 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(key: authkey);
686
687 if (mlen != sizeof(im)) {
688 ret = -ENOSPC;
689 goto out;
690 }
691
692 if (copy_from_user(to: &im, from: src, n: 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(p: 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: &im, upcall: &data->idmap_msg,
709 key: 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, ret: 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, ret: -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, type: "uid", id: &id, idmap);
753 if (ret == 0) {
754 *uid = make_kuid(from: idmap_userns(idmap), uid: id);
755 if (!uid_valid(uid: *uid))
756 ret = -ERANGE;
757 }
758 trace_nfs4_map_name_to_uid(nfs4_map_name_to_uid: name, len: namelen, id, error: 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, type: "gid", id: &id, idmap);
770 if (ret == 0) {
771 *gid = make_kgid(from: idmap_userns(idmap), gid: id);
772 if (!gid_valid(gid: *gid))
773 ret = -ERANGE;
774 }
775 trace_nfs4_map_group_to_gid(nfs4_map_group_to_gid: name, len: namelen, id, error: 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(to: idmap_userns(idmap), uid);
786 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
787 ret = nfs_idmap_lookup_name(id, type: "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(nfs4_map_uid_to_name: buf, len: ret, id, error: 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(to: idmap_userns(idmap), gid);
800 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
801 ret = nfs_idmap_lookup_name(id, type: "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(nfs4_map_gid_to_group: buf, len: ret, id, error: ret);
805 return ret;
806}
807

source code of linux/fs/nfs/nfs4idmap.c