4 * UID and GID to name mapping for clients.
6 * Copyright (c) 2002 The Regents of the University of Michigan.
9 * Marius Aamodt Eriksen <marius@umich.edu>
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
36 #include <linux/types.h>
37 #include <linux/parser.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>
53 #define NFS_UINT_MAXLEN 11
55 static const struct cred *id_resolver_cache;
56 static struct key_type key_type_id_resolver_legacy;
59 struct rpc_pipe *idmap_pipe;
60 struct key_construction *idmap_key_cons;
61 struct mutex idmap_mutex;
64 struct idmap_legacy_upcalldata {
65 struct rpc_pipe_msg pipe_msg;
66 struct idmap_msg idmap_msg;
71 * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
72 * @fattr: fully initialised struct nfs_fattr
73 * @owner_name: owner name string cache
74 * @group_name: group name string cache
76 void nfs_fattr_init_names(struct nfs_fattr *fattr,
77 struct nfs4_string *owner_name,
78 struct nfs4_string *group_name)
80 fattr->owner_name = owner_name;
81 fattr->group_name = group_name;
84 static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
86 fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
87 kfree(fattr->owner_name->data);
90 static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
92 fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
93 kfree(fattr->group_name->data);
96 static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
98 struct nfs4_string *owner = fattr->owner_name;
101 if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
103 if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
105 fattr->valid |= NFS_ATTR_FATTR_OWNER;
110 static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
112 struct nfs4_string *group = fattr->group_name;
115 if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
117 if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
119 fattr->valid |= NFS_ATTR_FATTR_GROUP;
125 * nfs_fattr_free_names - free up the NFSv4 owner and group strings
126 * @fattr: a fully initialised nfs_fattr structure
128 void nfs_fattr_free_names(struct nfs_fattr *fattr)
130 if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
131 nfs_fattr_free_owner_name(fattr);
132 if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
133 nfs_fattr_free_group_name(fattr);
137 * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
138 * @server: pointer to the filesystem nfs_server structure
139 * @fattr: a fully initialised nfs_fattr structure
141 * This helper maps the cached NFSv4 owner/group strings in fattr into
142 * their numeric uid/gid equivalents, and then frees the cached strings.
144 void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
146 if (nfs_fattr_map_owner_name(server, fattr))
147 nfs_fattr_free_owner_name(fattr);
148 if (nfs_fattr_map_group_name(server, fattr))
149 nfs_fattr_free_group_name(fattr);
152 static int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
157 if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
159 memcpy(buf, name, namelen);
161 if (kstrtoul(buf, 0, &val) != 0)
167 static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
169 return snprintf(buf, buflen, "%u", id);
172 static struct key_type key_type_id_resolver = {
173 .name = "id_resolver",
174 .instantiate = user_instantiate,
176 .revoke = user_revoke,
177 .destroy = user_destroy,
178 .describe = user_describe,
182 static int nfs_idmap_init_keyring(void)
188 printk(KERN_NOTICE "NFS: Registering the %s key type\n",
189 key_type_id_resolver.name);
191 cred = prepare_kernel_cred(NULL);
195 keyring = key_alloc(&key_type_keyring, ".id_resolver", 0, 0, cred,
196 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
197 KEY_USR_VIEW | KEY_USR_READ,
198 KEY_ALLOC_NOT_IN_QUOTA);
199 if (IS_ERR(keyring)) {
200 ret = PTR_ERR(keyring);
201 goto failed_put_cred;
204 ret = key_instantiate_and_link(keyring, NULL, 0, NULL, NULL);
208 ret = register_key_type(&key_type_id_resolver);
212 ret = register_key_type(&key_type_id_resolver_legacy);
214 goto failed_reg_legacy;
216 set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
217 cred->thread_keyring = keyring;
218 cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
219 id_resolver_cache = cred;
223 unregister_key_type(&key_type_id_resolver);
231 static void nfs_idmap_quit_keyring(void)
233 key_revoke(id_resolver_cache->thread_keyring);
234 unregister_key_type(&key_type_id_resolver);
235 unregister_key_type(&key_type_id_resolver_legacy);
236 put_cred(id_resolver_cache);
240 * Assemble the description to pass to request_key()
241 * This function will allocate a new string and update dest to point
242 * at it. The caller is responsible for freeing dest.
244 * On error 0 is returned. Otherwise, the length of dest is returned.
246 static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
247 const char *type, size_t typelen, char **desc)
250 size_t desclen = typelen + namelen + 2;
252 *desc = kmalloc(desclen, GFP_KERNEL);
257 memcpy(cp, type, typelen);
261 memcpy(cp, name, namelen);
267 static ssize_t nfs_idmap_request_key(struct key_type *key_type,
268 const char *name, size_t namelen,
269 const char *type, void *data,
270 size_t data_size, struct idmap *idmap)
272 const struct cred *saved_cred;
275 struct user_key_payload *payload;
278 ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
282 saved_cred = override_creds(id_resolver_cache);
284 rkey = request_key_with_auxdata(key_type, desc, "", 0, idmap);
286 rkey = request_key(&key_type_id_resolver, desc, "");
287 revert_creds(saved_cred);
296 rkey->perm |= KEY_USR_VIEW;
298 ret = key_validate(rkey);
302 payload = rcu_dereference(rkey->payload.data);
303 if (IS_ERR_OR_NULL(payload)) {
304 ret = PTR_ERR(payload);
308 ret = payload->datalen;
309 if (ret > 0 && ret <= data_size)
310 memcpy(data, payload->data, ret);
321 static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
322 const char *type, void *data,
323 size_t data_size, struct idmap *idmap)
325 ssize_t ret = nfs_idmap_request_key(&key_type_id_resolver,
326 name, namelen, type, data,
329 mutex_lock(&idmap->idmap_mutex);
330 ret = nfs_idmap_request_key(&key_type_id_resolver_legacy,
331 name, namelen, type, data,
333 idmap->idmap_key_cons = NULL;
334 mutex_unlock(&idmap->idmap_mutex);
340 static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
341 size_t buflen, struct idmap *idmap)
343 char id_str[NFS_UINT_MAXLEN];
347 id_len = snprintf(id_str, sizeof(id_str), "%u", id);
348 ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
355 static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
356 __u32 *id, struct idmap *idmap)
358 char id_str[NFS_UINT_MAXLEN];
363 data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
364 if (data_size <= 0) {
367 ret = kstrtol(id_str, 10, &id_long);
368 *id = (__u32)id_long;
373 /* idmap classic begins here */
376 Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
379 static const match_table_t nfs_idmap_tokens = {
380 { Opt_find_uid, "uid:%s" },
381 { Opt_find_gid, "gid:%s" },
382 { Opt_find_user, "user:%s" },
383 { Opt_find_group, "group:%s" },
384 { Opt_find_err, NULL }
387 static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *);
388 static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
390 static void idmap_release_pipe(struct inode *);
391 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
393 static const struct rpc_pipe_ops idmap_upcall_ops = {
394 .upcall = rpc_pipe_generic_upcall,
395 .downcall = idmap_pipe_downcall,
396 .release_pipe = idmap_release_pipe,
397 .destroy_msg = idmap_pipe_destroy_msg,
400 static struct key_type key_type_id_resolver_legacy = {
402 .instantiate = user_instantiate,
404 .revoke = user_revoke,
405 .destroy = user_destroy,
406 .describe = user_describe,
408 .request_key = nfs_idmap_legacy_upcall,
411 static void __nfs_idmap_unregister(struct rpc_pipe *pipe)
414 rpc_unlink(pipe->dentry);
417 static int __nfs_idmap_register(struct dentry *dir,
419 struct rpc_pipe *pipe)
421 struct dentry *dentry;
423 dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
425 return PTR_ERR(dentry);
426 pipe->dentry = dentry;
430 static void nfs_idmap_unregister(struct nfs_client *clp,
431 struct rpc_pipe *pipe)
433 struct net *net = clp->cl_net;
434 struct super_block *pipefs_sb;
436 pipefs_sb = rpc_get_sb_net(net);
438 __nfs_idmap_unregister(pipe);
443 static int nfs_idmap_register(struct nfs_client *clp,
445 struct rpc_pipe *pipe)
447 struct net *net = clp->cl_net;
448 struct super_block *pipefs_sb;
451 pipefs_sb = rpc_get_sb_net(net);
453 if (clp->cl_rpcclient->cl_dentry)
454 err = __nfs_idmap_register(clp->cl_rpcclient->cl_dentry,
462 nfs_idmap_new(struct nfs_client *clp)
465 struct rpc_pipe *pipe;
468 BUG_ON(clp->cl_idmap != NULL);
470 idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
474 pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
476 error = PTR_ERR(pipe);
480 error = nfs_idmap_register(clp, idmap, pipe);
482 rpc_destroy_pipe_data(pipe);
486 idmap->idmap_pipe = pipe;
487 mutex_init(&idmap->idmap_mutex);
489 clp->cl_idmap = idmap;
494 nfs_idmap_delete(struct nfs_client *clp)
496 struct idmap *idmap = clp->cl_idmap;
500 nfs_idmap_unregister(clp, idmap->idmap_pipe);
501 rpc_destroy_pipe_data(idmap->idmap_pipe);
502 clp->cl_idmap = NULL;
506 static int __rpc_pipefs_event(struct nfs_client *clp, unsigned long event,
507 struct super_block *sb)
512 case RPC_PIPEFS_MOUNT:
513 BUG_ON(clp->cl_rpcclient->cl_dentry == NULL);
514 err = __nfs_idmap_register(clp->cl_rpcclient->cl_dentry,
516 clp->cl_idmap->idmap_pipe);
518 case RPC_PIPEFS_UMOUNT:
519 if (clp->cl_idmap->idmap_pipe) {
520 struct dentry *parent;
522 parent = clp->cl_idmap->idmap_pipe->dentry->d_parent;
523 __nfs_idmap_unregister(clp->cl_idmap->idmap_pipe);
525 * Note: This is a dirty hack. SUNRPC hook has been
526 * called already but simple_rmdir() call for the
527 * directory returned with error because of idmap pipe
528 * inside. Thus now we have to remove this directory
531 if (rpc_rmdir(parent))
532 printk(KERN_ERR "NFS: %s: failed to remove "
533 "clnt dir!\n", __func__);
537 printk(KERN_ERR "NFS: %s: unknown event: %ld\n", __func__,
544 static struct nfs_client *nfs_get_client_for_event(struct net *net, int event)
546 struct nfs_net *nn = net_generic(net, nfs_net_id);
547 struct dentry *cl_dentry;
548 struct nfs_client *clp;
552 spin_lock(&nn->nfs_client_lock);
553 list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
554 /* Wait for initialisation to finish */
555 if (clp->cl_cons_state == NFS_CS_INITING) {
556 atomic_inc(&clp->cl_count);
557 spin_unlock(&nn->nfs_client_lock);
558 err = nfs_wait_client_init_complete(clp);
564 /* Skip nfs_clients that failed to initialise */
565 if (clp->cl_cons_state < 0)
568 if (clp->rpc_ops != &nfs_v4_clientops)
570 cl_dentry = clp->cl_idmap->idmap_pipe->dentry;
571 if (((event == RPC_PIPEFS_MOUNT) && cl_dentry) ||
572 ((event == RPC_PIPEFS_UMOUNT) && !cl_dentry))
574 atomic_inc(&clp->cl_count);
575 spin_unlock(&nn->nfs_client_lock);
578 spin_unlock(&nn->nfs_client_lock);
582 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
585 struct super_block *sb = ptr;
586 struct nfs_client *clp;
589 if (!try_module_get(THIS_MODULE))
592 while ((clp = nfs_get_client_for_event(sb->s_fs_info, event))) {
593 error = __rpc_pipefs_event(clp, event, sb);
598 module_put(THIS_MODULE);
602 #define PIPEFS_NFS_PRIO 1
604 static struct notifier_block nfs_idmap_block = {
605 .notifier_call = rpc_pipefs_event,
606 .priority = SUNRPC_PIPEFS_NFS_PRIO,
609 int nfs_idmap_init(void)
612 ret = nfs_idmap_init_keyring();
615 ret = rpc_pipefs_notifier_register(&nfs_idmap_block);
617 nfs_idmap_quit_keyring();
622 void nfs_idmap_quit(void)
624 rpc_pipefs_notifier_unregister(&nfs_idmap_block);
625 nfs_idmap_quit_keyring();
628 static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
629 struct idmap_msg *im,
630 struct rpc_pipe_msg *msg)
635 im->im_type = IDMAP_TYPE_GROUP;
636 token = match_token(desc, nfs_idmap_tokens, &substr);
640 im->im_type = IDMAP_TYPE_USER;
642 im->im_conv = IDMAP_CONV_NAMETOID;
643 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
647 im->im_type = IDMAP_TYPE_USER;
649 im->im_conv = IDMAP_CONV_IDTONAME;
650 ret = match_int(&substr, &im->im_id);
659 msg->len = sizeof(struct idmap_msg);
665 static int nfs_idmap_legacy_upcall(struct key_construction *cons,
669 struct idmap_legacy_upcalldata *data;
670 struct rpc_pipe_msg *msg;
671 struct idmap_msg *im;
672 struct idmap *idmap = (struct idmap *)aux;
673 struct key *key = cons->key;
676 /* msg and im are freed in idmap_pipe_destroy_msg */
677 data = kzalloc(sizeof(*data), GFP_KERNEL);
681 msg = &data->pipe_msg;
682 im = &data->idmap_msg;
685 ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
689 BUG_ON(idmap->idmap_key_cons != NULL);
690 idmap->idmap_key_cons = cons;
692 ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
699 idmap->idmap_key_cons = NULL;
703 complete_request_key(cons, ret);
707 static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data)
709 return key_instantiate_and_link(key, data, strlen(data) + 1,
710 id_resolver_cache->thread_keyring,
714 static int nfs_idmap_read_message(struct idmap_msg *im, struct key *key, struct key *authkey)
716 char id_str[NFS_UINT_MAXLEN];
719 switch (im->im_conv) {
720 case IDMAP_CONV_NAMETOID:
721 sprintf(id_str, "%d", im->im_id);
722 ret = nfs_idmap_instantiate(key, authkey, id_str);
724 case IDMAP_CONV_IDTONAME:
725 ret = nfs_idmap_instantiate(key, authkey, im->im_name);
733 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
735 struct rpc_inode *rpci = RPC_I(filp->f_path.dentry->d_inode);
736 struct idmap *idmap = (struct idmap *)rpci->private;
737 struct key_construction *cons;
742 /* If instantiation is successful, anyone waiting for key construction
743 * will have been woken up and someone else may now have used
744 * idmap_key_cons - so after this point we may no longer touch it.
746 cons = ACCESS_ONCE(idmap->idmap_key_cons);
747 idmap->idmap_key_cons = NULL;
749 if (mlen != sizeof(im)) {
754 if (copy_from_user(&im, src, mlen) != 0) {
759 if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
764 namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
765 if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
770 ret = nfs_idmap_read_message(&im, cons->key, cons->authkey);
772 key_set_timeout(cons->key, nfs_idmap_cache_timeout);
777 complete_request_key(cons, ret);
782 idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
784 struct idmap_legacy_upcalldata *data = container_of(msg,
785 struct idmap_legacy_upcalldata,
787 struct idmap *idmap = data->idmap;
788 struct key_construction *cons;
790 cons = ACCESS_ONCE(idmap->idmap_key_cons);
791 idmap->idmap_key_cons = NULL;
792 complete_request_key(cons, msg->errno);
794 /* Free memory allocated in nfs_idmap_legacy_upcall() */
799 idmap_release_pipe(struct inode *inode)
801 struct rpc_inode *rpci = RPC_I(inode);
802 struct idmap *idmap = (struct idmap *)rpci->private;
803 idmap->idmap_key_cons = NULL;
806 int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *uid)
808 struct idmap *idmap = server->nfs_client->cl_idmap;
810 if (nfs_map_string_to_numeric(name, namelen, uid))
812 return nfs_idmap_lookup_id(name, namelen, "uid", uid, idmap);
815 int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *gid)
817 struct idmap *idmap = server->nfs_client->cl_idmap;
819 if (nfs_map_string_to_numeric(name, namelen, gid))
821 return nfs_idmap_lookup_id(name, namelen, "gid", gid, idmap);
824 int nfs_map_uid_to_name(const struct nfs_server *server, __u32 uid, char *buf, size_t buflen)
826 struct idmap *idmap = server->nfs_client->cl_idmap;
829 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
830 ret = nfs_idmap_lookup_name(uid, "user", buf, buflen, idmap);
832 ret = nfs_map_numeric_to_string(uid, buf, buflen);
835 int nfs_map_gid_to_group(const struct nfs_server *server, __u32 gid, char *buf, size_t buflen)
837 struct idmap *idmap = server->nfs_client->cl_idmap;
840 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
841 ret = nfs_idmap_lookup_name(gid, "group", buf, buflen, idmap);
843 ret = nfs_map_numeric_to_string(gid, buf, buflen);