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
58 static const struct cred *id_resolver_cache;
59 static struct key_type key_type_id_resolver_legacy;
60
61 struct 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
68 struct 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
idmap_userns(const struct idmap * idmap)76 static 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 */
nfs_fattr_init_names(struct nfs_fattr * fattr,struct nfs4_string * owner_name,struct nfs4_string * group_name)89 void 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
nfs_fattr_free_owner_name(struct nfs_fattr * fattr)97 static 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
nfs_fattr_free_group_name(struct nfs_fattr * fattr)103 static 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
nfs_fattr_map_owner_name(struct nfs_server * server,struct nfs_fattr * fattr)109 static 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
nfs_fattr_map_group_name(struct nfs_server * server,struct nfs_fattr * fattr)123 static 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 */
nfs_fattr_free_names(struct nfs_fattr * fattr)141 void 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 */
nfs_fattr_map_and_free_names(struct nfs_server * server,struct nfs_fattr * fattr)157 void 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
nfs_map_string_to_numeric(const char * name,size_t namelen,__u32 * res)165 int 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 }
179 EXPORT_SYMBOL_GPL(nfs_map_string_to_numeric);
180
nfs_map_numeric_to_string(__u32 id,char * buf,size_t buflen)181 static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
182 {
183 return snprintf(buf, buflen, "%u", id);
184 }
185
186 static 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
nfs_idmap_init(void)197 int 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
234 failed_reg_legacy:
235 unregister_key_type(&key_type_id_resolver);
236 failed_put_key:
237 key_put(keyring);
238 failed_put_cred:
239 put_cred(cred);
240 return ret;
241 }
242
nfs_idmap_quit(void)243 void 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 */
nfs_idmap_get_desc(const char * name,size_t namelen,const char * type,size_t typelen,char ** desc)258 static 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
nfs_idmap_request_key(const char * name,size_t namelen,const char * type,struct idmap * idmap)279 static 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
nfs_idmap_get_key(const char * name,size_t namelen,const char * type,void * data,size_t data_size,struct idmap * idmap)305 static 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 struct key *rkey;
310 const struct user_key_payload *payload;
311 ssize_t ret;
312
313 scoped_with_creds(id_resolver_cache)
314 rkey = nfs_idmap_request_key(name, namelen, type, idmap);
315 if (IS_ERR(rkey)) {
316 ret = PTR_ERR(rkey);
317 goto out;
318 }
319
320 rcu_read_lock();
321 rkey->perm |= KEY_USR_VIEW;
322
323 ret = key_validate(rkey);
324 if (ret < 0)
325 goto out_up;
326
327 payload = user_key_payload_rcu(rkey);
328 if (IS_ERR_OR_NULL(payload)) {
329 ret = PTR_ERR(payload);
330 goto out_up;
331 }
332
333 ret = payload->datalen;
334 if (ret > 0 && ret <= data_size)
335 memcpy(data, payload->data, ret);
336 else
337 ret = -EINVAL;
338
339 out_up:
340 rcu_read_unlock();
341 key_put(rkey);
342 out:
343 return ret;
344 }
345
346 /* ID -> Name */
nfs_idmap_lookup_name(__u32 id,const char * type,char * buf,size_t buflen,struct idmap * idmap)347 static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
348 size_t buflen, struct idmap *idmap)
349 {
350 char id_str[NFS_UINT_MAXLEN];
351 int id_len;
352 ssize_t ret;
353
354 id_len = nfs_map_numeric_to_string(id, id_str, sizeof(id_str));
355 ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
356 if (ret < 0)
357 return -EINVAL;
358 return ret;
359 }
360
361 /* Name -> ID */
nfs_idmap_lookup_id(const char * name,size_t namelen,const char * type,__u32 * id,struct idmap * idmap)362 static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
363 __u32 *id, struct idmap *idmap)
364 {
365 char id_str[NFS_UINT_MAXLEN];
366 long id_long;
367 ssize_t data_size;
368 int ret = 0;
369
370 data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
371 if (data_size <= 0) {
372 ret = -EINVAL;
373 } else {
374 ret = kstrtol(id_str, 10, &id_long);
375 if (!ret)
376 *id = (__u32)id_long;
377 }
378 return ret;
379 }
380
381 /* idmap classic begins here */
382
383 enum {
384 Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
385 };
386
387 static const match_table_t nfs_idmap_tokens = {
388 { Opt_find_uid, "uid:%s" },
389 { Opt_find_gid, "gid:%s" },
390 { Opt_find_user, "user:%s" },
391 { Opt_find_group, "group:%s" },
392 { Opt_find_err, NULL }
393 };
394
395 static int nfs_idmap_legacy_upcall(struct key *, void *);
396 static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
397 size_t);
398 static void idmap_release_pipe(struct inode *);
399 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
400
401 static const struct rpc_pipe_ops idmap_upcall_ops = {
402 .upcall = rpc_pipe_generic_upcall,
403 .downcall = idmap_pipe_downcall,
404 .release_pipe = idmap_release_pipe,
405 .destroy_msg = idmap_pipe_destroy_msg,
406 };
407
408 static struct key_type key_type_id_resolver_legacy = {
409 .name = "id_legacy",
410 .preparse = user_preparse,
411 .free_preparse = user_free_preparse,
412 .instantiate = generic_key_instantiate,
413 .revoke = user_revoke,
414 .destroy = user_destroy,
415 .describe = user_describe,
416 .read = user_read,
417 .request_key = nfs_idmap_legacy_upcall,
418 };
419
nfs_idmap_pipe_destroy(struct dentry * dir,struct rpc_pipe_dir_object * pdo)420 static void nfs_idmap_pipe_destroy(struct dentry *dir,
421 struct rpc_pipe_dir_object *pdo)
422 {
423 struct idmap *idmap = pdo->pdo_data;
424
425 rpc_unlink(idmap->idmap_pipe);
426 }
427
nfs_idmap_pipe_create(struct dentry * dir,struct rpc_pipe_dir_object * pdo)428 static int nfs_idmap_pipe_create(struct dentry *dir,
429 struct rpc_pipe_dir_object *pdo)
430 {
431 struct idmap *idmap = pdo->pdo_data;
432
433 return rpc_mkpipe_dentry(dir, "idmap", idmap, idmap->idmap_pipe);
434 }
435
436 static const struct rpc_pipe_dir_object_ops nfs_idmap_pipe_dir_object_ops = {
437 .create = nfs_idmap_pipe_create,
438 .destroy = nfs_idmap_pipe_destroy,
439 };
440
441 int
nfs_idmap_new(struct nfs_client * clp)442 nfs_idmap_new(struct nfs_client *clp)
443 {
444 struct idmap *idmap;
445 struct rpc_pipe *pipe;
446 int error;
447
448 idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
449 if (idmap == NULL)
450 return -ENOMEM;
451
452 mutex_init(&idmap->idmap_mutex);
453 idmap->user_ns = get_user_ns(clp->cl_rpcclient->cl_cred->user_ns);
454
455 rpc_init_pipe_dir_object(&idmap->idmap_pdo,
456 &nfs_idmap_pipe_dir_object_ops,
457 idmap);
458
459 pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
460 if (IS_ERR(pipe)) {
461 error = PTR_ERR(pipe);
462 goto err;
463 }
464 idmap->idmap_pipe = pipe;
465
466 error = rpc_add_pipe_dir_object(clp->cl_net,
467 &clp->cl_rpcclient->cl_pipedir_objects,
468 &idmap->idmap_pdo);
469 if (error)
470 goto err_destroy_pipe;
471
472 clp->cl_idmap = idmap;
473 return 0;
474 err_destroy_pipe:
475 rpc_destroy_pipe_data(idmap->idmap_pipe);
476 err:
477 put_user_ns(idmap->user_ns);
478 kfree(idmap);
479 return error;
480 }
481
482 void
nfs_idmap_delete(struct nfs_client * clp)483 nfs_idmap_delete(struct nfs_client *clp)
484 {
485 struct idmap *idmap = clp->cl_idmap;
486
487 if (!idmap)
488 return;
489 clp->cl_idmap = NULL;
490 rpc_remove_pipe_dir_object(clp->cl_net,
491 &clp->cl_rpcclient->cl_pipedir_objects,
492 &idmap->idmap_pdo);
493 rpc_destroy_pipe_data(idmap->idmap_pipe);
494 put_user_ns(idmap->user_ns);
495 kfree(idmap);
496 }
497
nfs_idmap_prepare_message(char * desc,struct idmap * idmap,struct idmap_msg * im,struct rpc_pipe_msg * msg)498 static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
499 struct idmap_msg *im,
500 struct rpc_pipe_msg *msg)
501 {
502 substring_t substr;
503 int token, ret;
504
505 im->im_type = IDMAP_TYPE_GROUP;
506 token = match_token(desc, nfs_idmap_tokens, &substr);
507
508 switch (token) {
509 case Opt_find_uid:
510 im->im_type = IDMAP_TYPE_USER;
511 fallthrough;
512 case Opt_find_gid:
513 im->im_conv = IDMAP_CONV_NAMETOID;
514 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
515 break;
516
517 case Opt_find_user:
518 im->im_type = IDMAP_TYPE_USER;
519 fallthrough;
520 case Opt_find_group:
521 im->im_conv = IDMAP_CONV_IDTONAME;
522 ret = match_int(&substr, &im->im_id);
523 if (ret)
524 goto out;
525 break;
526
527 default:
528 ret = -EINVAL;
529 goto out;
530 }
531
532 msg->data = im;
533 msg->len = sizeof(struct idmap_msg);
534
535 out:
536 return ret;
537 }
538
539 static bool
nfs_idmap_prepare_pipe_upcall(struct idmap * idmap,struct idmap_legacy_upcalldata * data)540 nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
541 struct idmap_legacy_upcalldata *data)
542 {
543 if (idmap->idmap_upcall_data != NULL) {
544 WARN_ON_ONCE(1);
545 return false;
546 }
547 idmap->idmap_upcall_data = data;
548 return true;
549 }
550
nfs_idmap_complete_pipe_upcall(struct idmap_legacy_upcalldata * data,int ret)551 static void nfs_idmap_complete_pipe_upcall(struct idmap_legacy_upcalldata *data,
552 int ret)
553 {
554 complete_request_key(data->authkey, ret);
555 key_put(data->authkey);
556 kfree(data);
557 }
558
nfs_idmap_abort_pipe_upcall(struct idmap * idmap,struct idmap_legacy_upcalldata * data,int ret)559 static void nfs_idmap_abort_pipe_upcall(struct idmap *idmap,
560 struct idmap_legacy_upcalldata *data,
561 int ret)
562 {
563 if (cmpxchg(&idmap->idmap_upcall_data, data, NULL) == data)
564 nfs_idmap_complete_pipe_upcall(data, ret);
565 }
566
nfs_idmap_legacy_upcall(struct key * authkey,void * aux)567 static int nfs_idmap_legacy_upcall(struct key *authkey, void *aux)
568 {
569 struct idmap_legacy_upcalldata *data;
570 struct request_key_auth *rka = get_request_key_auth(authkey);
571 struct rpc_pipe_msg *msg;
572 struct idmap_msg *im;
573 struct idmap *idmap = aux;
574 struct key *key = rka->target_key;
575 int ret = -ENOKEY;
576
577 if (!aux)
578 goto out1;
579
580 /* msg and im are freed in idmap_pipe_destroy_msg */
581 ret = -ENOMEM;
582 data = kzalloc(sizeof(*data), GFP_KERNEL);
583 if (!data)
584 goto out1;
585
586 msg = &data->pipe_msg;
587 im = &data->idmap_msg;
588 data->idmap = idmap;
589 data->authkey = key_get(authkey);
590
591 ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
592 if (ret < 0)
593 goto out2;
594
595 ret = -EAGAIN;
596 if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
597 goto out2;
598
599 ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
600 if (ret < 0)
601 nfs_idmap_abort_pipe_upcall(idmap, data, ret);
602
603 return ret;
604 out2:
605 kfree(data);
606 out1:
607 complete_request_key(authkey, ret);
608 return ret;
609 }
610
nfs_idmap_instantiate(struct key * key,struct key * authkey,char * data,size_t datalen)611 static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
612 {
613 return key_instantiate_and_link(key, data, datalen,
614 id_resolver_cache->thread_keyring,
615 authkey);
616 }
617
nfs_idmap_read_and_verify_message(struct idmap_msg * im,struct idmap_msg * upcall,struct key * key,struct key * authkey)618 static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
619 struct idmap_msg *upcall,
620 struct key *key, struct key *authkey)
621 {
622 char id_str[NFS_UINT_MAXLEN];
623 size_t len;
624 int ret = -ENOKEY;
625
626 /* ret = -ENOKEY */
627 if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
628 goto out;
629 switch (im->im_conv) {
630 case IDMAP_CONV_NAMETOID:
631 if (strcmp(upcall->im_name, im->im_name) != 0)
632 break;
633 /* Note: here we store the NUL terminator too */
634 len = 1 + nfs_map_numeric_to_string(im->im_id, id_str,
635 sizeof(id_str));
636 ret = nfs_idmap_instantiate(key, authkey, id_str, len);
637 break;
638 case IDMAP_CONV_IDTONAME:
639 if (upcall->im_id != im->im_id)
640 break;
641 len = strlen(im->im_name);
642 ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
643 break;
644 default:
645 ret = -EINVAL;
646 }
647 out:
648 return ret;
649 }
650
651 static ssize_t
idmap_pipe_downcall(struct file * filp,const char __user * src,size_t mlen)652 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
653 {
654 struct request_key_auth *rka;
655 struct rpc_inode *rpci = RPC_I(file_inode(filp));
656 struct idmap *idmap = (struct idmap *)rpci->private;
657 struct idmap_legacy_upcalldata *data;
658 struct key *authkey;
659 struct idmap_msg im;
660 size_t namelen_in;
661 int ret = -ENOKEY;
662
663 /* If instantiation is successful, anyone waiting for key construction
664 * will have been woken up and someone else may now have used
665 * idmap_key_cons - so after this point we may no longer touch it.
666 */
667 data = xchg(&idmap->idmap_upcall_data, NULL);
668 if (data == NULL)
669 goto out_noupcall;
670
671 authkey = data->authkey;
672 rka = get_request_key_auth(authkey);
673
674 if (mlen != sizeof(im)) {
675 ret = -ENOSPC;
676 goto out;
677 }
678
679 if (copy_from_user(&im, src, mlen) != 0) {
680 ret = -EFAULT;
681 goto out;
682 }
683
684 if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
685 ret = -ENOKEY;
686 goto out;
687 }
688
689 namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
690 if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
691 ret = -EINVAL;
692 goto out;
693 }
694
695 ret = nfs_idmap_read_and_verify_message(&im, &data->idmap_msg,
696 rka->target_key, authkey);
697 if (ret >= 0) {
698 key_set_timeout(rka->target_key, nfs_idmap_cache_timeout);
699 ret = mlen;
700 }
701
702 out:
703 nfs_idmap_complete_pipe_upcall(data, ret);
704 out_noupcall:
705 return ret;
706 }
707
708 static void
idmap_pipe_destroy_msg(struct rpc_pipe_msg * msg)709 idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
710 {
711 struct idmap_legacy_upcalldata *data = container_of(msg,
712 struct idmap_legacy_upcalldata,
713 pipe_msg);
714 struct idmap *idmap = data->idmap;
715
716 if (msg->errno)
717 nfs_idmap_abort_pipe_upcall(idmap, data, msg->errno);
718 }
719
720 static void
idmap_release_pipe(struct inode * inode)721 idmap_release_pipe(struct inode *inode)
722 {
723 struct rpc_inode *rpci = RPC_I(inode);
724 struct idmap *idmap = (struct idmap *)rpci->private;
725 struct idmap_legacy_upcalldata *data;
726
727 data = xchg(&idmap->idmap_upcall_data, NULL);
728 if (data)
729 nfs_idmap_complete_pipe_upcall(data, -EPIPE);
730 }
731
nfs_map_name_to_uid(const struct nfs_server * server,const char * name,size_t namelen,kuid_t * uid)732 int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
733 {
734 struct idmap *idmap = server->nfs_client->cl_idmap;
735 __u32 id = -1;
736 int ret = 0;
737
738 if (!nfs_map_string_to_numeric(name, namelen, &id))
739 ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
740 if (ret == 0) {
741 *uid = make_kuid(idmap_userns(idmap), id);
742 if (!uid_valid(*uid))
743 ret = -ERANGE;
744 }
745 trace_nfs4_map_name_to_uid(name, namelen, id, ret);
746 return ret;
747 }
748
nfs_map_group_to_gid(const struct nfs_server * server,const char * name,size_t namelen,kgid_t * gid)749 int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
750 {
751 struct idmap *idmap = server->nfs_client->cl_idmap;
752 __u32 id = -1;
753 int ret = 0;
754
755 if (!nfs_map_string_to_numeric(name, namelen, &id))
756 ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
757 if (ret == 0) {
758 *gid = make_kgid(idmap_userns(idmap), id);
759 if (!gid_valid(*gid))
760 ret = -ERANGE;
761 }
762 trace_nfs4_map_group_to_gid(name, namelen, id, ret);
763 return ret;
764 }
765
nfs_map_uid_to_name(const struct nfs_server * server,kuid_t uid,char * buf,size_t buflen)766 int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
767 {
768 struct idmap *idmap = server->nfs_client->cl_idmap;
769 int ret = -EINVAL;
770 __u32 id;
771
772 id = from_kuid_munged(idmap_userns(idmap), uid);
773 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
774 ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
775 if (ret < 0)
776 ret = nfs_map_numeric_to_string(id, buf, buflen);
777 trace_nfs4_map_uid_to_name(buf, ret, id, ret);
778 return ret;
779 }
nfs_map_gid_to_group(const struct nfs_server * server,kgid_t gid,char * buf,size_t buflen)780 int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
781 {
782 struct idmap *idmap = server->nfs_client->cl_idmap;
783 int ret = -EINVAL;
784 __u32 id;
785
786 id = from_kgid_munged(idmap_userns(idmap), gid);
787 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
788 ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
789 if (ret < 0)
790 ret = nfs_map_numeric_to_string(id, buf, buflen);
791 trace_nfs4_map_gid_to_group(buf, ret, id, ret);
792 return ret;
793 }
794