~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/nfs/idmap.c

Version: ~ [ linux-5.5 ] ~ [ linux-5.4.15 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.98 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.167 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.211 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.211 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.81 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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 <linux/nfs_idmap.h>
 40 #include <net/net_namespace.h>
 41 #include <linux/sunrpc/rpc_pipe_fs.h>
 42 #include <linux/nfs_fs.h>
 43 #include <linux/nfs_fs_sb.h>
 44 #include <linux/key.h>
 45 #include <linux/keyctl.h>
 46 #include <linux/key-type.h>
 47 #include <keys/user-type.h>
 48 #include <linux/module.h>
 49 
 50 #include "internal.h"
 51 #include "netns.h"
 52 
 53 #define NFS_UINT_MAXLEN 11
 54 
 55 static const struct cred *id_resolver_cache;
 56 static struct key_type key_type_id_resolver_legacy;
 57 
 58 struct idmap_legacy_upcalldata {
 59         struct rpc_pipe_msg pipe_msg;
 60         struct idmap_msg idmap_msg;
 61         struct key_construction *key_cons;
 62         struct idmap *idmap;
 63 };
 64 
 65 struct idmap {
 66         struct rpc_pipe         *idmap_pipe;
 67         struct idmap_legacy_upcalldata *idmap_upcall_data;
 68         struct mutex            idmap_mutex;
 69 };
 70 
 71 /**
 72  * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
 73  * @fattr: fully initialised struct nfs_fattr
 74  * @owner_name: owner name string cache
 75  * @group_name: group name string cache
 76  */
 77 void nfs_fattr_init_names(struct nfs_fattr *fattr,
 78                 struct nfs4_string *owner_name,
 79                 struct nfs4_string *group_name)
 80 {
 81         fattr->owner_name = owner_name;
 82         fattr->group_name = group_name;
 83 }
 84 
 85 static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
 86 {
 87         fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
 88         kfree(fattr->owner_name->data);
 89 }
 90 
 91 static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
 92 {
 93         fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
 94         kfree(fattr->group_name->data);
 95 }
 96 
 97 static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
 98 {
 99         struct nfs4_string *owner = fattr->owner_name;
100         kuid_t uid;
101 
102         if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
103                 return false;
104         if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
105                 fattr->uid = uid;
106                 fattr->valid |= NFS_ATTR_FATTR_OWNER;
107         }
108         return true;
109 }
110 
111 static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
112 {
113         struct nfs4_string *group = fattr->group_name;
114         kgid_t gid;
115 
116         if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
117                 return false;
118         if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
119                 fattr->gid = gid;
120                 fattr->valid |= NFS_ATTR_FATTR_GROUP;
121         }
122         return true;
123 }
124 
125 /**
126  * nfs_fattr_free_names - free up the NFSv4 owner and group strings
127  * @fattr: a fully initialised nfs_fattr structure
128  */
129 void nfs_fattr_free_names(struct nfs_fattr *fattr)
130 {
131         if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
132                 nfs_fattr_free_owner_name(fattr);
133         if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
134                 nfs_fattr_free_group_name(fattr);
135 }
136 
137 /**
138  * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
139  * @server: pointer to the filesystem nfs_server structure
140  * @fattr: a fully initialised nfs_fattr structure
141  *
142  * This helper maps the cached NFSv4 owner/group strings in fattr into
143  * their numeric uid/gid equivalents, and then frees the cached strings.
144  */
145 void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
146 {
147         if (nfs_fattr_map_owner_name(server, fattr))
148                 nfs_fattr_free_owner_name(fattr);
149         if (nfs_fattr_map_group_name(server, fattr))
150                 nfs_fattr_free_group_name(fattr);
151 }
152 
153 static int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
154 {
155         unsigned long val;
156         char buf[16];
157 
158         if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
159                 return 0;
160         memcpy(buf, name, namelen);
161         buf[namelen] = '\0';
162         if (kstrtoul(buf, 0, &val) != 0)
163                 return 0;
164         *res = val;
165         return 1;
166 }
167 
168 static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
169 {
170         return snprintf(buf, buflen, "%u", id);
171 }
172 
173 static struct key_type key_type_id_resolver = {
174         .name           = "id_resolver",
175         .instantiate    = user_instantiate,
176         .match          = user_match,
177         .revoke         = user_revoke,
178         .destroy        = user_destroy,
179         .describe       = user_describe,
180         .read           = user_read,
181 };
182 
183 static int nfs_idmap_init_keyring(void)
184 {
185         struct cred *cred;
186         struct key *keyring;
187         int ret = 0;
188 
189         printk(KERN_NOTICE "NFS: Registering the %s key type\n",
190                 key_type_id_resolver.name);
191 
192         cred = prepare_kernel_cred(NULL);
193         if (!cred)
194                 return -ENOMEM;
195 
196         keyring = keyring_alloc(".id_resolver",
197                                 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
198                                 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
199                                 KEY_USR_VIEW | KEY_USR_READ,
200                                 KEY_ALLOC_NOT_IN_QUOTA, NULL);
201         if (IS_ERR(keyring)) {
202                 ret = PTR_ERR(keyring);
203                 goto failed_put_cred;
204         }
205 
206         ret = register_key_type(&key_type_id_resolver);
207         if (ret < 0)
208                 goto failed_put_key;
209 
210         ret = register_key_type(&key_type_id_resolver_legacy);
211         if (ret < 0)
212                 goto failed_reg_legacy;
213 
214         set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
215         cred->thread_keyring = keyring;
216         cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
217         id_resolver_cache = cred;
218         return 0;
219 
220 failed_reg_legacy:
221         unregister_key_type(&key_type_id_resolver);
222 failed_put_key:
223         key_put(keyring);
224 failed_put_cred:
225         put_cred(cred);
226         return ret;
227 }
228 
229 static void nfs_idmap_quit_keyring(void)
230 {
231         key_revoke(id_resolver_cache->thread_keyring);
232         unregister_key_type(&key_type_id_resolver);
233         unregister_key_type(&key_type_id_resolver_legacy);
234         put_cred(id_resolver_cache);
235 }
236 
237 /*
238  * Assemble the description to pass to request_key()
239  * This function will allocate a new string and update dest to point
240  * at it.  The caller is responsible for freeing dest.
241  *
242  * On error 0 is returned.  Otherwise, the length of dest is returned.
243  */
244 static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
245                                 const char *type, size_t typelen, char **desc)
246 {
247         char *cp;
248         size_t desclen = typelen + namelen + 2;
249 
250         *desc = kmalloc(desclen, GFP_KERNEL);
251         if (!*desc)
252                 return -ENOMEM;
253 
254         cp = *desc;
255         memcpy(cp, type, typelen);
256         cp += typelen;
257         *cp++ = ':';
258 
259         memcpy(cp, name, namelen);
260         cp += namelen;
261         *cp = '\0';
262         return desclen;
263 }
264 
265 static ssize_t nfs_idmap_request_key(struct key_type *key_type,
266                                      const char *name, size_t namelen,
267                                      const char *type, void *data,
268                                      size_t data_size, struct idmap *idmap)
269 {
270         const struct cred *saved_cred;
271         struct key *rkey;
272         char *desc;
273         struct user_key_payload *payload;
274         ssize_t ret;
275 
276         ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
277         if (ret <= 0)
278                 goto out;
279 
280         saved_cred = override_creds(id_resolver_cache);
281         if (idmap)
282                 rkey = request_key_with_auxdata(key_type, desc, "", 0, idmap);
283         else
284                 rkey = request_key(&key_type_id_resolver, desc, "");
285         revert_creds(saved_cred);
286 
287         kfree(desc);
288         if (IS_ERR(rkey)) {
289                 ret = PTR_ERR(rkey);
290                 goto out;
291         }
292 
293         rcu_read_lock();
294         rkey->perm |= KEY_USR_VIEW;
295 
296         ret = key_validate(rkey);
297         if (ret < 0)
298                 goto out_up;
299 
300         payload = rcu_dereference(rkey->payload.data);
301         if (IS_ERR_OR_NULL(payload)) {
302                 ret = PTR_ERR(payload);
303                 goto out_up;
304         }
305 
306         ret = payload->datalen;
307         if (ret > 0 && ret <= data_size)
308                 memcpy(data, payload->data, ret);
309         else
310                 ret = -EINVAL;
311 
312 out_up:
313         rcu_read_unlock();
314         key_put(rkey);
315 out:
316         return ret;
317 }
318 
319 static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
320                                  const char *type, void *data,
321                                  size_t data_size, struct idmap *idmap)
322 {
323         ssize_t ret = nfs_idmap_request_key(&key_type_id_resolver,
324                                             name, namelen, type, data,
325                                             data_size, NULL);
326         if (ret < 0) {
327                 mutex_lock(&idmap->idmap_mutex);
328                 ret = nfs_idmap_request_key(&key_type_id_resolver_legacy,
329                                             name, namelen, type, data,
330                                             data_size, idmap);
331                 mutex_unlock(&idmap->idmap_mutex);
332         }
333         return ret;
334 }
335 
336 /* ID -> Name */
337 static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
338                                      size_t buflen, struct idmap *idmap)
339 {
340         char id_str[NFS_UINT_MAXLEN];
341         int id_len;
342         ssize_t ret;
343 
344         id_len = snprintf(id_str, sizeof(id_str), "%u", id);
345         ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
346         if (ret < 0)
347                 return -EINVAL;
348         return ret;
349 }
350 
351 /* Name -> ID */
352 static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
353                                __u32 *id, struct idmap *idmap)
354 {
355         char id_str[NFS_UINT_MAXLEN];
356         long id_long;
357         ssize_t data_size;
358         int ret = 0;
359 
360         data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
361         if (data_size <= 0) {
362                 ret = -EINVAL;
363         } else {
364                 ret = kstrtol(id_str, 10, &id_long);
365                 *id = (__u32)id_long;
366         }
367         return ret;
368 }
369 
370 /* idmap classic begins here */
371 
372 enum {
373         Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
374 };
375 
376 static const match_table_t nfs_idmap_tokens = {
377         { Opt_find_uid, "uid:%s" },
378         { Opt_find_gid, "gid:%s" },
379         { Opt_find_user, "user:%s" },
380         { Opt_find_group, "group:%s" },
381         { Opt_find_err, NULL }
382 };
383 
384 static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *);
385 static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
386                                    size_t);
387 static void idmap_release_pipe(struct inode *);
388 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
389 
390 static const struct rpc_pipe_ops idmap_upcall_ops = {
391         .upcall         = rpc_pipe_generic_upcall,
392         .downcall       = idmap_pipe_downcall,
393         .release_pipe   = idmap_release_pipe,
394         .destroy_msg    = idmap_pipe_destroy_msg,
395 };
396 
397 static struct key_type key_type_id_resolver_legacy = {
398         .name           = "id_legacy",
399         .instantiate    = user_instantiate,
400         .match          = user_match,
401         .revoke         = user_revoke,
402         .destroy        = user_destroy,
403         .describe       = user_describe,
404         .read           = user_read,
405         .request_key    = nfs_idmap_legacy_upcall,
406 };
407 
408 static void __nfs_idmap_unregister(struct rpc_pipe *pipe)
409 {
410         if (pipe->dentry)
411                 rpc_unlink(pipe->dentry);
412 }
413 
414 static int __nfs_idmap_register(struct dentry *dir,
415                                      struct idmap *idmap,
416                                      struct rpc_pipe *pipe)
417 {
418         struct dentry *dentry;
419 
420         dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
421         if (IS_ERR(dentry))
422                 return PTR_ERR(dentry);
423         pipe->dentry = dentry;
424         return 0;
425 }
426 
427 static void nfs_idmap_unregister(struct nfs_client *clp,
428                                       struct rpc_pipe *pipe)
429 {
430         struct net *net = clp->cl_net;
431         struct super_block *pipefs_sb;
432 
433         pipefs_sb = rpc_get_sb_net(net);
434         if (pipefs_sb) {
435                 __nfs_idmap_unregister(pipe);
436                 rpc_put_sb_net(net);
437         }
438 }
439 
440 static int nfs_idmap_register(struct nfs_client *clp,
441                                    struct idmap *idmap,
442                                    struct rpc_pipe *pipe)
443 {
444         struct net *net = clp->cl_net;
445         struct super_block *pipefs_sb;
446         int err = 0;
447 
448         pipefs_sb = rpc_get_sb_net(net);
449         if (pipefs_sb) {
450                 if (clp->cl_rpcclient->cl_dentry)
451                         err = __nfs_idmap_register(clp->cl_rpcclient->cl_dentry,
452                                                    idmap, pipe);
453                 rpc_put_sb_net(net);
454         }
455         return err;
456 }
457 
458 int
459 nfs_idmap_new(struct nfs_client *clp)
460 {
461         struct idmap *idmap;
462         struct rpc_pipe *pipe;
463         int error;
464 
465         idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
466         if (idmap == NULL)
467                 return -ENOMEM;
468 
469         pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
470         if (IS_ERR(pipe)) {
471                 error = PTR_ERR(pipe);
472                 kfree(idmap);
473                 return error;
474         }
475         error = nfs_idmap_register(clp, idmap, pipe);
476         if (error) {
477                 rpc_destroy_pipe_data(pipe);
478                 kfree(idmap);
479                 return error;
480         }
481         idmap->idmap_pipe = pipe;
482         mutex_init(&idmap->idmap_mutex);
483 
484         clp->cl_idmap = idmap;
485         return 0;
486 }
487 
488 void
489 nfs_idmap_delete(struct nfs_client *clp)
490 {
491         struct idmap *idmap = clp->cl_idmap;
492 
493         if (!idmap)
494                 return;
495         nfs_idmap_unregister(clp, idmap->idmap_pipe);
496         rpc_destroy_pipe_data(idmap->idmap_pipe);
497         clp->cl_idmap = NULL;
498         kfree(idmap);
499 }
500 
501 static int __rpc_pipefs_event(struct nfs_client *clp, unsigned long event,
502                               struct super_block *sb)
503 {
504         int err = 0;
505 
506         switch (event) {
507         case RPC_PIPEFS_MOUNT:
508                 err = __nfs_idmap_register(clp->cl_rpcclient->cl_dentry,
509                                                 clp->cl_idmap,
510                                                 clp->cl_idmap->idmap_pipe);
511                 break;
512         case RPC_PIPEFS_UMOUNT:
513                 if (clp->cl_idmap->idmap_pipe) {
514                         struct dentry *parent;
515 
516                         parent = clp->cl_idmap->idmap_pipe->dentry->d_parent;
517                         __nfs_idmap_unregister(clp->cl_idmap->idmap_pipe);
518                         /*
519                          * Note: This is a dirty hack. SUNRPC hook has been
520                          * called already but simple_rmdir() call for the
521                          * directory returned with error because of idmap pipe
522                          * inside. Thus now we have to remove this directory
523                          * here.
524                          */
525                         if (rpc_rmdir(parent))
526                                 printk(KERN_ERR "NFS: %s: failed to remove "
527                                         "clnt dir!\n", __func__);
528                 }
529                 break;
530         default:
531                 printk(KERN_ERR "NFS: %s: unknown event: %ld\n", __func__,
532                         event);
533                 return -ENOTSUPP;
534         }
535         return err;
536 }
537 
538 static struct nfs_client *nfs_get_client_for_event(struct net *net, int event)
539 {
540         struct nfs_net *nn = net_generic(net, nfs_net_id);
541         struct dentry *cl_dentry;
542         struct nfs_client *clp;
543         int err;
544 
545 restart:
546         spin_lock(&nn->nfs_client_lock);
547         list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
548                 /* Wait for initialisation to finish */
549                 if (clp->cl_cons_state == NFS_CS_INITING) {
550                         atomic_inc(&clp->cl_count);
551                         spin_unlock(&nn->nfs_client_lock);
552                         err = nfs_wait_client_init_complete(clp);
553                         nfs_put_client(clp);
554                         if (err)
555                                 return NULL;
556                         goto restart;
557                 }
558                 /* Skip nfs_clients that failed to initialise */
559                 if (clp->cl_cons_state < 0)
560                         continue;
561                 smp_rmb();
562                 if (clp->rpc_ops != &nfs_v4_clientops)
563                         continue;
564                 cl_dentry = clp->cl_idmap->idmap_pipe->dentry;
565                 if (((event == RPC_PIPEFS_MOUNT) && cl_dentry) ||
566                     ((event == RPC_PIPEFS_UMOUNT) && !cl_dentry))
567                         continue;
568                 atomic_inc(&clp->cl_count);
569                 spin_unlock(&nn->nfs_client_lock);
570                 return clp;
571         }
572         spin_unlock(&nn->nfs_client_lock);
573         return NULL;
574 }
575 
576 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
577                             void *ptr)
578 {
579         struct super_block *sb = ptr;
580         struct nfs_client *clp;
581         int error = 0;
582 
583         if (!try_module_get(THIS_MODULE))
584                 return 0;
585 
586         while ((clp = nfs_get_client_for_event(sb->s_fs_info, event))) {
587                 error = __rpc_pipefs_event(clp, event, sb);
588                 nfs_put_client(clp);
589                 if (error)
590                         break;
591         }
592         module_put(THIS_MODULE);
593         return error;
594 }
595 
596 #define PIPEFS_NFS_PRIO         1
597 
598 static struct notifier_block nfs_idmap_block = {
599         .notifier_call  = rpc_pipefs_event,
600         .priority       = SUNRPC_PIPEFS_NFS_PRIO,
601 };
602 
603 int nfs_idmap_init(void)
604 {
605         int ret;
606         ret = nfs_idmap_init_keyring();
607         if (ret != 0)
608                 goto out;
609         ret = rpc_pipefs_notifier_register(&nfs_idmap_block);
610         if (ret != 0)
611                 nfs_idmap_quit_keyring();
612 out:
613         return ret;
614 }
615 
616 void nfs_idmap_quit(void)
617 {
618         rpc_pipefs_notifier_unregister(&nfs_idmap_block);
619         nfs_idmap_quit_keyring();
620 }
621 
622 static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
623                                      struct idmap_msg *im,
624                                      struct rpc_pipe_msg *msg)
625 {
626         substring_t substr;
627         int token, ret;
628 
629         im->im_type = IDMAP_TYPE_GROUP;
630         token = match_token(desc, nfs_idmap_tokens, &substr);
631 
632         switch (token) {
633         case Opt_find_uid:
634                 im->im_type = IDMAP_TYPE_USER;
635         case Opt_find_gid:
636                 im->im_conv = IDMAP_CONV_NAMETOID;
637                 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
638                 break;
639 
640         case Opt_find_user:
641                 im->im_type = IDMAP_TYPE_USER;
642         case Opt_find_group:
643                 im->im_conv = IDMAP_CONV_IDTONAME;
644                 ret = match_int(&substr, &im->im_id);
645                 break;
646 
647         default:
648                 ret = -EINVAL;
649                 goto out;
650         }
651 
652         msg->data = im;
653         msg->len  = sizeof(struct idmap_msg);
654 
655 out:
656         return ret;
657 }
658 
659 static bool
660 nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
661                 struct idmap_legacy_upcalldata *data)
662 {
663         if (idmap->idmap_upcall_data != NULL) {
664                 WARN_ON_ONCE(1);
665                 return false;
666         }
667         idmap->idmap_upcall_data = data;
668         return true;
669 }
670 
671 static void
672 nfs_idmap_complete_pipe_upcall_locked(struct idmap *idmap, int ret)
673 {
674         struct key_construction *cons = idmap->idmap_upcall_data->key_cons;
675 
676         kfree(idmap->idmap_upcall_data);
677         idmap->idmap_upcall_data = NULL;
678         complete_request_key(cons, ret);
679 }
680 
681 static void
682 nfs_idmap_abort_pipe_upcall(struct idmap *idmap, int ret)
683 {
684         if (idmap->idmap_upcall_data != NULL)
685                 nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
686 }
687 
688 static int nfs_idmap_legacy_upcall(struct key_construction *cons,
689                                    const char *op,
690                                    void *aux)
691 {
692         struct idmap_legacy_upcalldata *data;
693         struct rpc_pipe_msg *msg;
694         struct idmap_msg *im;
695         struct idmap *idmap = (struct idmap *)aux;
696         struct key *key = cons->key;
697         int ret = -ENOMEM;
698 
699         /* msg and im are freed in idmap_pipe_destroy_msg */
700         data = kzalloc(sizeof(*data), GFP_KERNEL);
701         if (!data)
702                 goto out1;
703 
704         msg = &data->pipe_msg;
705         im = &data->idmap_msg;
706         data->idmap = idmap;
707         data->key_cons = cons;
708 
709         ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
710         if (ret < 0)
711                 goto out2;
712 
713         ret = -EAGAIN;
714         if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
715                 goto out2;
716 
717         ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
718         if (ret < 0)
719                 nfs_idmap_abort_pipe_upcall(idmap, ret);
720 
721         return ret;
722 out2:
723         kfree(data);
724 out1:
725         complete_request_key(cons, ret);
726         return ret;
727 }
728 
729 static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
730 {
731         return key_instantiate_and_link(key, data, datalen,
732                                         id_resolver_cache->thread_keyring,
733                                         authkey);
734 }
735 
736 static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
737                 struct idmap_msg *upcall,
738                 struct key *key, struct key *authkey)
739 {
740         char id_str[NFS_UINT_MAXLEN];
741         size_t len;
742         int ret = -ENOKEY;
743 
744         /* ret = -ENOKEY */
745         if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
746                 goto out;
747         switch (im->im_conv) {
748         case IDMAP_CONV_NAMETOID:
749                 if (strcmp(upcall->im_name, im->im_name) != 0)
750                         break;
751                 /* Note: here we store the NUL terminator too */
752                 len = sprintf(id_str, "%d", im->im_id) + 1;
753                 ret = nfs_idmap_instantiate(key, authkey, id_str, len);
754                 break;
755         case IDMAP_CONV_IDTONAME:
756                 if (upcall->im_id != im->im_id)
757                         break;
758                 len = strlen(im->im_name);
759                 ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
760                 break;
761         default:
762                 ret = -EINVAL;
763         }
764 out:
765         return ret;
766 }
767 
768 static ssize_t
769 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
770 {
771         struct rpc_inode *rpci = RPC_I(file_inode(filp));
772         struct idmap *idmap = (struct idmap *)rpci->private;
773         struct key_construction *cons;
774         struct idmap_msg im;
775         size_t namelen_in;
776         int ret = -ENOKEY;
777 
778         /* If instantiation is successful, anyone waiting for key construction
779          * will have been woken up and someone else may now have used
780          * idmap_key_cons - so after this point we may no longer touch it.
781          */
782         if (idmap->idmap_upcall_data == NULL)
783                 goto out_noupcall;
784 
785         cons = idmap->idmap_upcall_data->key_cons;
786 
787         if (mlen != sizeof(im)) {
788                 ret = -ENOSPC;
789                 goto out;
790         }
791 
792         if (copy_from_user(&im, src, mlen) != 0) {
793                 ret = -EFAULT;
794                 goto out;
795         }
796 
797         if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
798                 ret = -ENOKEY;
799                 goto out;
800         }
801 
802         namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
803         if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
804                 ret = -EINVAL;
805                 goto out;
806 }
807 
808         ret = nfs_idmap_read_and_verify_message(&im,
809                         &idmap->idmap_upcall_data->idmap_msg,
810                         cons->key, cons->authkey);
811         if (ret >= 0) {
812                 key_set_timeout(cons->key, nfs_idmap_cache_timeout);
813                 ret = mlen;
814         }
815 
816 out:
817         nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
818 out_noupcall:
819         return ret;
820 }
821 
822 static void
823 idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
824 {
825         struct idmap_legacy_upcalldata *data = container_of(msg,
826                         struct idmap_legacy_upcalldata,
827                         pipe_msg);
828         struct idmap *idmap = data->idmap;
829 
830         if (msg->errno)
831                 nfs_idmap_abort_pipe_upcall(idmap, msg->errno);
832 }
833 
834 static void
835 idmap_release_pipe(struct inode *inode)
836 {
837         struct rpc_inode *rpci = RPC_I(inode);
838         struct idmap *idmap = (struct idmap *)rpci->private;
839 
840         nfs_idmap_abort_pipe_upcall(idmap, -EPIPE);
841 }
842 
843 int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
844 {
845         struct idmap *idmap = server->nfs_client->cl_idmap;
846         __u32 id = -1;
847         int ret = 0;
848 
849         if (!nfs_map_string_to_numeric(name, namelen, &id))
850                 ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
851         if (ret == 0) {
852                 *uid = make_kuid(&init_user_ns, id);
853                 if (!uid_valid(*uid))
854                         ret = -ERANGE;
855         }
856         return ret;
857 }
858 
859 int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
860 {
861         struct idmap *idmap = server->nfs_client->cl_idmap;
862         __u32 id = -1;
863         int ret = 0;
864 
865         if (!nfs_map_string_to_numeric(name, namelen, &id))
866                 ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
867         if (ret == 0) {
868                 *gid = make_kgid(&init_user_ns, id);
869                 if (!gid_valid(*gid))
870                         ret = -ERANGE;
871         }
872         return ret;
873 }
874 
875 int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
876 {
877         struct idmap *idmap = server->nfs_client->cl_idmap;
878         int ret = -EINVAL;
879         __u32 id;
880 
881         id = from_kuid(&init_user_ns, uid);
882         if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
883                 ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
884         if (ret < 0)
885                 ret = nfs_map_numeric_to_string(id, buf, buflen);
886         return ret;
887 }
888 int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
889 {
890         struct idmap *idmap = server->nfs_client->cl_idmap;
891         int ret = -EINVAL;
892         __u32 id;
893 
894         id = from_kgid(&init_user_ns, gid);
895         if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
896                 ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
897         if (ret < 0)
898                 ret = nfs_map_numeric_to_string(id, buf, buflen);
899         return ret;
900 }
901 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp