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 /* Default cache timeout is 10 minutes */
56 unsigned int nfs_idmap_cache_timeout = 600;
57 static const struct cred *id_resolver_cache;
58 static struct key_type key_type_id_resolver_legacy;
62 * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
63 * @fattr: fully initialised struct nfs_fattr
64 * @owner_name: owner name string cache
65 * @group_name: group name string cache
67 void nfs_fattr_init_names(struct nfs_fattr *fattr,
68 struct nfs4_string *owner_name,
69 struct nfs4_string *group_name)
71 fattr->owner_name = owner_name;
72 fattr->group_name = group_name;
75 static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
77 fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
78 kfree(fattr->owner_name->data);
81 static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
83 fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
84 kfree(fattr->group_name->data);
87 static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
89 struct nfs4_string *owner = fattr->owner_name;
92 if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
94 if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
96 fattr->valid |= NFS_ATTR_FATTR_OWNER;
101 static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
103 struct nfs4_string *group = fattr->group_name;
106 if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
108 if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
110 fattr->valid |= NFS_ATTR_FATTR_GROUP;
116 * nfs_fattr_free_names - free up the NFSv4 owner and group strings
117 * @fattr: a fully initialised nfs_fattr structure
119 void nfs_fattr_free_names(struct nfs_fattr *fattr)
121 if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
122 nfs_fattr_free_owner_name(fattr);
123 if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
124 nfs_fattr_free_group_name(fattr);
128 * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
129 * @server: pointer to the filesystem nfs_server structure
130 * @fattr: a fully initialised nfs_fattr structure
132 * This helper maps the cached NFSv4 owner/group strings in fattr into
133 * their numeric uid/gid equivalents, and then frees the cached strings.
135 void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
137 if (nfs_fattr_map_owner_name(server, fattr))
138 nfs_fattr_free_owner_name(fattr);
139 if (nfs_fattr_map_group_name(server, fattr))
140 nfs_fattr_free_group_name(fattr);
143 static int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
148 if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
150 memcpy(buf, name, namelen);
152 if (strict_strtoul(buf, 0, &val) != 0)
158 static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
160 return snprintf(buf, buflen, "%u", id);
163 static struct key_type key_type_id_resolver = {
164 .name = "id_resolver",
165 .instantiate = user_instantiate,
167 .revoke = user_revoke,
168 .destroy = user_destroy,
169 .describe = user_describe,
173 static int nfs_idmap_init_keyring(void)
179 printk(KERN_NOTICE "NFS: Registering the %s key type\n",
180 key_type_id_resolver.name);
182 cred = prepare_kernel_cred(NULL);
186 keyring = key_alloc(&key_type_keyring, ".id_resolver", 0, 0, cred,
187 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
188 KEY_USR_VIEW | KEY_USR_READ,
189 KEY_ALLOC_NOT_IN_QUOTA);
190 if (IS_ERR(keyring)) {
191 ret = PTR_ERR(keyring);
192 goto failed_put_cred;
195 ret = key_instantiate_and_link(keyring, NULL, 0, NULL, NULL);
199 ret = register_key_type(&key_type_id_resolver);
203 set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
204 cred->thread_keyring = keyring;
205 cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
206 id_resolver_cache = cred;
216 static void nfs_idmap_quit_keyring(void)
218 key_revoke(id_resolver_cache->thread_keyring);
219 unregister_key_type(&key_type_id_resolver);
220 put_cred(id_resolver_cache);
224 * Assemble the description to pass to request_key()
225 * This function will allocate a new string and update dest to point
226 * at it. The caller is responsible for freeing dest.
228 * On error 0 is returned. Otherwise, the length of dest is returned.
230 static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
231 const char *type, size_t typelen, char **desc)
234 size_t desclen = typelen + namelen + 2;
236 *desc = kmalloc(desclen, GFP_KERNEL);
241 memcpy(cp, type, typelen);
245 memcpy(cp, name, namelen);
251 static ssize_t nfs_idmap_request_key(struct key_type *key_type,
252 const char *name, size_t namelen,
253 const char *type, void *data,
254 size_t data_size, struct idmap *idmap)
256 const struct cred *saved_cred;
259 struct user_key_payload *payload;
262 ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
266 saved_cred = override_creds(id_resolver_cache);
268 rkey = request_key_with_auxdata(key_type, desc, "", 0, idmap);
270 rkey = request_key(&key_type_id_resolver, desc, "");
271 revert_creds(saved_cred);
280 rkey->perm |= KEY_USR_VIEW;
282 ret = key_validate(rkey);
286 payload = rcu_dereference(rkey->payload.data);
287 if (IS_ERR_OR_NULL(payload)) {
288 ret = PTR_ERR(payload);
292 ret = payload->datalen;
293 if (ret > 0 && ret <= data_size)
294 memcpy(data, payload->data, ret);
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)
309 ssize_t ret = nfs_idmap_request_key(&key_type_id_resolver,
310 name, namelen, type, data,
313 ret = nfs_idmap_request_key(&key_type_id_resolver_legacy,
314 name, namelen, type, data,
321 static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
322 size_t buflen, struct idmap *idmap)
324 char id_str[NFS_UINT_MAXLEN];
328 id_len = snprintf(id_str, sizeof(id_str), "%u", id);
329 ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
336 static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
337 __u32 *id, struct idmap *idmap)
339 char id_str[NFS_UINT_MAXLEN];
344 data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
345 if (data_size <= 0) {
348 ret = strict_strtol(id_str, 10, &id_long);
349 *id = (__u32)id_long;
354 /* idmap classic begins here */
355 module_param(nfs_idmap_cache_timeout, int, 0644);
358 struct rpc_pipe *idmap_pipe;
359 struct key_construction *idmap_key_cons;
363 Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
366 static const match_table_t nfs_idmap_tokens = {
367 { Opt_find_uid, "uid:%s" },
368 { Opt_find_gid, "gid:%s" },
369 { Opt_find_user, "user:%s" },
370 { Opt_find_group, "group:%s" },
371 { Opt_find_err, NULL }
374 static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *);
375 static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
377 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
379 static const struct rpc_pipe_ops idmap_upcall_ops = {
380 .upcall = rpc_pipe_generic_upcall,
381 .downcall = idmap_pipe_downcall,
382 .destroy_msg = idmap_pipe_destroy_msg,
385 static struct key_type key_type_id_resolver_legacy = {
386 .name = "id_resolver",
387 .instantiate = user_instantiate,
389 .revoke = user_revoke,
390 .destroy = user_destroy,
391 .describe = user_describe,
393 .request_key = nfs_idmap_legacy_upcall,
396 static void __nfs_idmap_unregister(struct rpc_pipe *pipe)
399 rpc_unlink(pipe->dentry);
402 static int __nfs_idmap_register(struct dentry *dir,
404 struct rpc_pipe *pipe)
406 struct dentry *dentry;
408 dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
410 return PTR_ERR(dentry);
411 pipe->dentry = dentry;
415 static void nfs_idmap_unregister(struct nfs_client *clp,
416 struct rpc_pipe *pipe)
418 struct net *net = clp->net;
419 struct super_block *pipefs_sb;
421 pipefs_sb = rpc_get_sb_net(net);
423 __nfs_idmap_unregister(pipe);
428 static int nfs_idmap_register(struct nfs_client *clp,
430 struct rpc_pipe *pipe)
432 struct net *net = clp->net;
433 struct super_block *pipefs_sb;
436 pipefs_sb = rpc_get_sb_net(net);
438 if (clp->cl_rpcclient->cl_dentry)
439 err = __nfs_idmap_register(clp->cl_rpcclient->cl_dentry,
447 nfs_idmap_new(struct nfs_client *clp)
450 struct rpc_pipe *pipe;
453 BUG_ON(clp->cl_idmap != NULL);
455 idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
459 pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
461 error = PTR_ERR(pipe);
465 error = nfs_idmap_register(clp, idmap, pipe);
467 rpc_destroy_pipe_data(pipe);
471 idmap->idmap_pipe = pipe;
473 clp->cl_idmap = idmap;
478 nfs_idmap_delete(struct nfs_client *clp)
480 struct idmap *idmap = clp->cl_idmap;
484 nfs_idmap_unregister(clp, idmap->idmap_pipe);
485 rpc_destroy_pipe_data(idmap->idmap_pipe);
486 clp->cl_idmap = NULL;
490 static int __rpc_pipefs_event(struct nfs_client *clp, unsigned long event,
491 struct super_block *sb)
496 case RPC_PIPEFS_MOUNT:
497 BUG_ON(clp->cl_rpcclient->cl_dentry == NULL);
498 err = __nfs_idmap_register(clp->cl_rpcclient->cl_dentry,
500 clp->cl_idmap->idmap_pipe);
502 case RPC_PIPEFS_UMOUNT:
503 if (clp->cl_idmap->idmap_pipe) {
504 struct dentry *parent;
506 parent = clp->cl_idmap->idmap_pipe->dentry->d_parent;
507 __nfs_idmap_unregister(clp->cl_idmap->idmap_pipe);
509 * Note: This is a dirty hack. SUNRPC hook has been
510 * called already but simple_rmdir() call for the
511 * directory returned with error because of idmap pipe
512 * inside. Thus now we have to remove this directory
515 if (rpc_rmdir(parent))
516 printk(KERN_ERR "NFS: %s: failed to remove "
517 "clnt dir!\n", __func__);
521 printk(KERN_ERR "NFS: %s: unknown event: %ld\n", __func__,
528 static struct nfs_client *nfs_get_client_for_event(struct net *net, int event)
530 struct nfs_net *nn = net_generic(net, nfs_net_id);
531 struct dentry *cl_dentry;
532 struct nfs_client *clp;
534 spin_lock(&nn->nfs_client_lock);
535 list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
536 if (clp->rpc_ops != &nfs_v4_clientops)
538 cl_dentry = clp->cl_idmap->idmap_pipe->dentry;
539 if (((event == RPC_PIPEFS_MOUNT) && cl_dentry) ||
540 ((event == RPC_PIPEFS_UMOUNT) && !cl_dentry))
542 atomic_inc(&clp->cl_count);
543 spin_unlock(&nn->nfs_client_lock);
546 spin_unlock(&nn->nfs_client_lock);
550 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
553 struct super_block *sb = ptr;
554 struct nfs_client *clp;
557 if (!try_module_get(THIS_MODULE))
560 while ((clp = nfs_get_client_for_event(sb->s_fs_info, event))) {
561 error = __rpc_pipefs_event(clp, event, sb);
566 module_put(THIS_MODULE);
570 #define PIPEFS_NFS_PRIO 1
572 static struct notifier_block nfs_idmap_block = {
573 .notifier_call = rpc_pipefs_event,
574 .priority = SUNRPC_PIPEFS_NFS_PRIO,
577 int nfs_idmap_init(void)
580 ret = nfs_idmap_init_keyring();
583 ret = rpc_pipefs_notifier_register(&nfs_idmap_block);
585 nfs_idmap_quit_keyring();
590 void nfs_idmap_quit(void)
592 rpc_pipefs_notifier_unregister(&nfs_idmap_block);
593 nfs_idmap_quit_keyring();
596 static int nfs_idmap_prepare_message(char *desc, struct idmap_msg *im,
597 struct rpc_pipe_msg *msg)
602 memset(im, 0, sizeof(*im));
603 memset(msg, 0, sizeof(*msg));
605 im->im_type = IDMAP_TYPE_GROUP;
606 token = match_token(desc, nfs_idmap_tokens, &substr);
610 im->im_type = IDMAP_TYPE_USER;
612 im->im_conv = IDMAP_CONV_NAMETOID;
613 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
617 im->im_type = IDMAP_TYPE_USER;
619 im->im_conv = IDMAP_CONV_IDTONAME;
620 ret = match_int(&substr, &im->im_id);
629 msg->len = sizeof(struct idmap_msg);
635 static int nfs_idmap_legacy_upcall(struct key_construction *cons,
639 struct rpc_pipe_msg *msg;
640 struct idmap_msg *im;
641 struct idmap *idmap = (struct idmap *)aux;
642 struct key *key = cons->key;
645 /* msg and im are freed in idmap_pipe_destroy_msg */
646 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
652 im = kmalloc(sizeof(*im), GFP_KERNEL);
658 ret = nfs_idmap_prepare_message(key->description, im, msg);
662 idmap->idmap_key_cons = cons;
664 ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
675 key_revoke(cons->key);
676 key_revoke(cons->authkey);
680 static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data)
682 return key_instantiate_and_link(key, data, strlen(data) + 1,
683 id_resolver_cache->thread_keyring,
687 static int nfs_idmap_read_message(struct idmap_msg *im, struct key *key, struct key *authkey)
689 char id_str[NFS_UINT_MAXLEN];
692 switch (im->im_conv) {
693 case IDMAP_CONV_NAMETOID:
694 sprintf(id_str, "%d", im->im_id);
695 ret = nfs_idmap_instantiate(key, authkey, id_str);
697 case IDMAP_CONV_IDTONAME:
698 ret = nfs_idmap_instantiate(key, authkey, im->im_name);
706 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
708 struct rpc_inode *rpci = RPC_I(filp->f_path.dentry->d_inode);
709 struct idmap *idmap = (struct idmap *)rpci->private;
710 struct key_construction *cons = idmap->idmap_key_cons;
715 if (mlen != sizeof(im)) {
720 if (copy_from_user(&im, src, mlen) != 0) {
725 if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
727 complete_request_key(idmap->idmap_key_cons, -ENOKEY);
731 namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
732 if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
737 ret = nfs_idmap_read_message(&im, cons->key, cons->authkey);
739 key_set_timeout(cons->key, nfs_idmap_cache_timeout);
744 complete_request_key(idmap->idmap_key_cons, ret);
750 idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
752 /* Free memory allocated in nfs_idmap_legacy_upcall() */
757 int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *uid)
759 struct idmap *idmap = server->nfs_client->cl_idmap;
761 if (nfs_map_string_to_numeric(name, namelen, uid))
763 return nfs_idmap_lookup_id(name, namelen, "uid", uid, idmap);
766 int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *gid)
768 struct idmap *idmap = server->nfs_client->cl_idmap;
770 if (nfs_map_string_to_numeric(name, namelen, gid))
772 return nfs_idmap_lookup_id(name, namelen, "gid", gid, idmap);
775 int nfs_map_uid_to_name(const struct nfs_server *server, __u32 uid, char *buf, size_t buflen)
777 struct idmap *idmap = server->nfs_client->cl_idmap;
780 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
781 ret = nfs_idmap_lookup_name(uid, "user", buf, buflen, idmap);
783 ret = nfs_map_numeric_to_string(uid, buf, buflen);
786 int nfs_map_gid_to_group(const struct nfs_server *server, __u32 gid, char *buf, size_t buflen)
788 struct idmap *idmap = server->nfs_client->cl_idmap;
791 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
792 ret = nfs_idmap_lookup_name(gid, "group", buf, buflen, idmap);
794 ret = nfs_map_numeric_to_string(gid, buf, buflen);