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 <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 <linux/module.h>
51 #include "nfs4idmap.h"
52 #include "nfs4trace.h"
54 #define NFS_UINT_MAXLEN 11
56 static const struct cred *id_resolver_cache;
57 static struct key_type key_type_id_resolver_legacy;
59 struct idmap_legacy_upcalldata {
60 struct rpc_pipe_msg pipe_msg;
61 struct idmap_msg idmap_msg;
62 struct key_construction *key_cons;
67 struct rpc_pipe_dir_object idmap_pdo;
68 struct rpc_pipe *idmap_pipe;
69 struct idmap_legacy_upcalldata *idmap_upcall_data;
70 struct mutex idmap_mutex;
74 * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
75 * @fattr: fully initialised struct nfs_fattr
76 * @owner_name: owner name string cache
77 * @group_name: group name string cache
79 void nfs_fattr_init_names(struct nfs_fattr *fattr,
80 struct nfs4_string *owner_name,
81 struct nfs4_string *group_name)
83 fattr->owner_name = owner_name;
84 fattr->group_name = group_name;
87 static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
89 fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
90 kfree(fattr->owner_name->data);
93 static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
95 fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
96 kfree(fattr->group_name->data);
99 static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
101 struct nfs4_string *owner = fattr->owner_name;
104 if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
106 if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
108 fattr->valid |= NFS_ATTR_FATTR_OWNER;
113 static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
115 struct nfs4_string *group = fattr->group_name;
118 if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
120 if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
122 fattr->valid |= NFS_ATTR_FATTR_GROUP;
128 * nfs_fattr_free_names - free up the NFSv4 owner and group strings
129 * @fattr: a fully initialised nfs_fattr structure
131 void nfs_fattr_free_names(struct nfs_fattr *fattr)
133 if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
134 nfs_fattr_free_owner_name(fattr);
135 if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
136 nfs_fattr_free_group_name(fattr);
140 * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
141 * @server: pointer to the filesystem nfs_server structure
142 * @fattr: a fully initialised nfs_fattr structure
144 * This helper maps the cached NFSv4 owner/group strings in fattr into
145 * their numeric uid/gid equivalents, and then frees the cached strings.
147 void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
149 if (nfs_fattr_map_owner_name(server, fattr))
150 nfs_fattr_free_owner_name(fattr);
151 if (nfs_fattr_map_group_name(server, fattr))
152 nfs_fattr_free_group_name(fattr);
155 int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
160 if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
162 memcpy(buf, name, namelen);
164 if (kstrtoul(buf, 0, &val) != 0)
169 EXPORT_SYMBOL_GPL(nfs_map_string_to_numeric);
171 static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
173 return snprintf(buf, buflen, "%u", id);
176 static struct key_type key_type_id_resolver = {
177 .name = "id_resolver",
178 .preparse = user_preparse,
179 .free_preparse = user_free_preparse,
180 .instantiate = generic_key_instantiate,
181 .revoke = user_revoke,
182 .destroy = user_destroy,
183 .describe = user_describe,
187 int nfs_idmap_init(void)
193 printk(KERN_NOTICE "NFS: Registering the %s key type\n",
194 key_type_id_resolver.name);
196 cred = prepare_kernel_cred(NULL);
200 keyring = keyring_alloc(".id_resolver",
201 GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
202 (KEY_POS_ALL & ~KEY_POS_SETATTR) |
203 KEY_USR_VIEW | KEY_USR_READ,
204 KEY_ALLOC_NOT_IN_QUOTA, NULL);
205 if (IS_ERR(keyring)) {
206 ret = PTR_ERR(keyring);
207 goto failed_put_cred;
210 ret = register_key_type(&key_type_id_resolver);
214 ret = register_key_type(&key_type_id_resolver_legacy);
216 goto failed_reg_legacy;
218 set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
219 cred->thread_keyring = keyring;
220 cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
221 id_resolver_cache = cred;
225 unregister_key_type(&key_type_id_resolver);
233 void nfs_idmap_quit(void)
235 key_revoke(id_resolver_cache->thread_keyring);
236 unregister_key_type(&key_type_id_resolver);
237 unregister_key_type(&key_type_id_resolver_legacy);
238 put_cred(id_resolver_cache);
242 * Assemble the description to pass to request_key()
243 * This function will allocate a new string and update dest to point
244 * at it. The caller is responsible for freeing dest.
246 * On error 0 is returned. Otherwise, the length of dest is returned.
248 static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
249 const char *type, size_t typelen, char **desc)
252 size_t desclen = typelen + namelen + 2;
254 *desc = kmalloc(desclen, GFP_KERNEL);
259 memcpy(cp, type, typelen);
263 memcpy(cp, name, namelen);
269 static struct key *nfs_idmap_request_key(const char *name, size_t namelen,
270 const char *type, struct idmap *idmap)
276 ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
280 rkey = request_key(&key_type_id_resolver, desc, "");
282 mutex_lock(&idmap->idmap_mutex);
283 rkey = request_key_with_auxdata(&key_type_id_resolver_legacy,
285 mutex_unlock(&idmap->idmap_mutex);
288 set_bit(KEY_FLAG_ROOT_CAN_INVAL, &rkey->flags);
294 static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
295 const char *type, void *data,
296 size_t data_size, struct idmap *idmap)
298 const struct cred *saved_cred;
300 struct user_key_payload *payload;
303 saved_cred = override_creds(id_resolver_cache);
304 rkey = nfs_idmap_request_key(name, namelen, type, idmap);
305 revert_creds(saved_cred);
313 rkey->perm |= KEY_USR_VIEW;
315 ret = key_validate(rkey);
319 payload = rcu_dereference(rkey->payload.rcudata);
320 if (IS_ERR_OR_NULL(payload)) {
321 ret = PTR_ERR(payload);
325 ret = payload->datalen;
326 if (ret > 0 && ret <= data_size)
327 memcpy(data, payload->data, ret);
339 static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
340 size_t buflen, struct idmap *idmap)
342 char id_str[NFS_UINT_MAXLEN];
346 id_len = snprintf(id_str, sizeof(id_str), "%u", id);
347 ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
354 static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
355 __u32 *id, struct idmap *idmap)
357 char id_str[NFS_UINT_MAXLEN];
362 data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
363 if (data_size <= 0) {
366 ret = kstrtol(id_str, 10, &id_long);
367 *id = (__u32)id_long;
372 /* idmap classic begins here */
375 Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
378 static const match_table_t nfs_idmap_tokens = {
379 { Opt_find_uid, "uid:%s" },
380 { Opt_find_gid, "gid:%s" },
381 { Opt_find_user, "user:%s" },
382 { Opt_find_group, "group:%s" },
383 { Opt_find_err, NULL }
386 static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *);
387 static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
389 static void idmap_release_pipe(struct inode *);
390 static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
392 static const struct rpc_pipe_ops idmap_upcall_ops = {
393 .upcall = rpc_pipe_generic_upcall,
394 .downcall = idmap_pipe_downcall,
395 .release_pipe = idmap_release_pipe,
396 .destroy_msg = idmap_pipe_destroy_msg,
399 static struct key_type key_type_id_resolver_legacy = {
401 .preparse = user_preparse,
402 .free_preparse = user_free_preparse,
403 .instantiate = generic_key_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_pipe_destroy(struct dentry *dir,
412 struct rpc_pipe_dir_object *pdo)
414 struct idmap *idmap = pdo->pdo_data;
415 struct rpc_pipe *pipe = idmap->idmap_pipe;
418 rpc_unlink(pipe->dentry);
423 static int nfs_idmap_pipe_create(struct dentry *dir,
424 struct rpc_pipe_dir_object *pdo)
426 struct idmap *idmap = pdo->pdo_data;
427 struct rpc_pipe *pipe = idmap->idmap_pipe;
428 struct dentry *dentry;
430 dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
432 return PTR_ERR(dentry);
433 pipe->dentry = dentry;
437 static const struct rpc_pipe_dir_object_ops nfs_idmap_pipe_dir_object_ops = {
438 .create = nfs_idmap_pipe_create,
439 .destroy = nfs_idmap_pipe_destroy,
443 nfs_idmap_new(struct nfs_client *clp)
446 struct rpc_pipe *pipe;
449 idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
453 rpc_init_pipe_dir_object(&idmap->idmap_pdo,
454 &nfs_idmap_pipe_dir_object_ops,
457 pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
459 error = PTR_ERR(pipe);
462 idmap->idmap_pipe = pipe;
463 mutex_init(&idmap->idmap_mutex);
465 error = rpc_add_pipe_dir_object(clp->cl_net,
466 &clp->cl_rpcclient->cl_pipedir_objects,
469 goto err_destroy_pipe;
471 clp->cl_idmap = idmap;
474 rpc_destroy_pipe_data(idmap->idmap_pipe);
481 nfs_idmap_delete(struct nfs_client *clp)
483 struct idmap *idmap = clp->cl_idmap;
487 clp->cl_idmap = NULL;
488 rpc_remove_pipe_dir_object(clp->cl_net,
489 &clp->cl_rpcclient->cl_pipedir_objects,
491 rpc_destroy_pipe_data(idmap->idmap_pipe);
495 static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
496 struct idmap_msg *im,
497 struct rpc_pipe_msg *msg)
502 im->im_type = IDMAP_TYPE_GROUP;
503 token = match_token(desc, nfs_idmap_tokens, &substr);
507 im->im_type = IDMAP_TYPE_USER;
509 im->im_conv = IDMAP_CONV_NAMETOID;
510 ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
514 im->im_type = IDMAP_TYPE_USER;
516 im->im_conv = IDMAP_CONV_IDTONAME;
517 ret = match_int(&substr, &im->im_id);
526 msg->len = sizeof(struct idmap_msg);
533 nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
534 struct idmap_legacy_upcalldata *data)
536 if (idmap->idmap_upcall_data != NULL) {
540 idmap->idmap_upcall_data = data;
545 nfs_idmap_complete_pipe_upcall_locked(struct idmap *idmap, int ret)
547 struct key_construction *cons = idmap->idmap_upcall_data->key_cons;
549 kfree(idmap->idmap_upcall_data);
550 idmap->idmap_upcall_data = NULL;
551 complete_request_key(cons, ret);
555 nfs_idmap_abort_pipe_upcall(struct idmap *idmap, int ret)
557 if (idmap->idmap_upcall_data != NULL)
558 nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
561 static int nfs_idmap_legacy_upcall(struct key_construction *cons,
565 struct idmap_legacy_upcalldata *data;
566 struct rpc_pipe_msg *msg;
567 struct idmap_msg *im;
568 struct idmap *idmap = (struct idmap *)aux;
569 struct key *key = cons->key;
572 /* msg and im are freed in idmap_pipe_destroy_msg */
573 data = kzalloc(sizeof(*data), GFP_KERNEL);
577 msg = &data->pipe_msg;
578 im = &data->idmap_msg;
580 data->key_cons = cons;
582 ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
587 if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
590 ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
592 nfs_idmap_abort_pipe_upcall(idmap, ret);
598 complete_request_key(cons, ret);
602 static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
604 return key_instantiate_and_link(key, data, datalen,
605 id_resolver_cache->thread_keyring,
609 static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
610 struct idmap_msg *upcall,
611 struct key *key, struct key *authkey)
613 char id_str[NFS_UINT_MAXLEN];
618 if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
620 switch (im->im_conv) {
621 case IDMAP_CONV_NAMETOID:
622 if (strcmp(upcall->im_name, im->im_name) != 0)
624 /* Note: here we store the NUL terminator too */
625 len = sprintf(id_str, "%d", im->im_id) + 1;
626 ret = nfs_idmap_instantiate(key, authkey, id_str, len);
628 case IDMAP_CONV_IDTONAME:
629 if (upcall->im_id != im->im_id)
631 len = strlen(im->im_name);
632 ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
642 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
644 struct rpc_inode *rpci = RPC_I(file_inode(filp));
645 struct idmap *idmap = (struct idmap *)rpci->private;
646 struct key_construction *cons;
651 /* If instantiation is successful, anyone waiting for key construction
652 * will have been woken up and someone else may now have used
653 * idmap_key_cons - so after this point we may no longer touch it.
655 if (idmap->idmap_upcall_data == NULL)
658 cons = idmap->idmap_upcall_data->key_cons;
660 if (mlen != sizeof(im)) {
665 if (copy_from_user(&im, src, mlen) != 0) {
670 if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
675 namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
676 if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
681 ret = nfs_idmap_read_and_verify_message(&im,
682 &idmap->idmap_upcall_data->idmap_msg,
683 cons->key, cons->authkey);
685 key_set_timeout(cons->key, nfs_idmap_cache_timeout);
690 nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
696 idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
698 struct idmap_legacy_upcalldata *data = container_of(msg,
699 struct idmap_legacy_upcalldata,
701 struct idmap *idmap = data->idmap;
704 nfs_idmap_abort_pipe_upcall(idmap, msg->errno);
708 idmap_release_pipe(struct inode *inode)
710 struct rpc_inode *rpci = RPC_I(inode);
711 struct idmap *idmap = (struct idmap *)rpci->private;
713 nfs_idmap_abort_pipe_upcall(idmap, -EPIPE);
716 int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
718 struct idmap *idmap = server->nfs_client->cl_idmap;
722 if (!nfs_map_string_to_numeric(name, namelen, &id))
723 ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
725 *uid = make_kuid(&init_user_ns, id);
726 if (!uid_valid(*uid))
729 trace_nfs4_map_name_to_uid(name, namelen, id, ret);
733 int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
735 struct idmap *idmap = server->nfs_client->cl_idmap;
739 if (!nfs_map_string_to_numeric(name, namelen, &id))
740 ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
742 *gid = make_kgid(&init_user_ns, id);
743 if (!gid_valid(*gid))
746 trace_nfs4_map_group_to_gid(name, namelen, id, ret);
750 int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
752 struct idmap *idmap = server->nfs_client->cl_idmap;
756 id = from_kuid(&init_user_ns, uid);
757 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
758 ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
760 ret = nfs_map_numeric_to_string(id, buf, buflen);
761 trace_nfs4_map_uid_to_name(buf, ret, id, ret);
764 int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
766 struct idmap *idmap = server->nfs_client->cl_idmap;
770 id = from_kgid(&init_user_ns, gid);
771 if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
772 ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
774 ret = nfs_map_numeric_to_string(id, buf, buflen);
775 trace_nfs4_map_gid_to_group(buf, ret, id, ret);