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