2 * linux/fs/nfsd/nfs4recover.c
4 * Copyright (c) 2004 The Regents of the University of Michigan.
7 * Andy Adamson <andros@citi.umich.edu>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 #include <linux/file.h>
37 #include <linux/namei.h>
38 #include <linux/crypto.h>
39 #include <linux/sched.h>
45 #define NFSDDBG_FACILITY NFSDDBG_PROC
48 static struct path rec_dir;
49 static int rec_dir_init = 0;
52 nfs4_save_creds(const struct cred **original_creds)
56 new = prepare_creds();
62 *original_creds = override_creds(new);
68 nfs4_reset_creds(const struct cred *original)
70 revert_creds(original);
74 md5_to_hex(char *out, char *md5)
78 for (i=0; i<16; i++) {
79 unsigned char c = md5[i];
81 *out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
82 *out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
88 nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname)
90 struct xdr_netobj cksum;
91 struct hash_desc desc;
92 struct scatterlist sg;
93 __be32 status = nfserr_resource;
95 dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
96 clname->len, clname->data);
97 desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
98 desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
101 cksum.len = crypto_hash_digestsize(desc.tfm);
102 cksum.data = kmalloc(cksum.len, GFP_KERNEL);
103 if (cksum.data == NULL)
106 sg_init_one(&sg, clname->data, clname->len);
108 if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
111 md5_to_hex(dname, cksum.data);
116 crypto_free_hash(desc.tfm);
122 nfsd4_sync_rec_dir(void)
124 mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
125 nfsd_sync_dir(rec_dir.dentry);
126 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
130 nfsd4_create_clid_dir(struct nfs4_client *clp)
132 const struct cred *original_cred;
133 char *dname = clp->cl_recdir;
134 struct dentry *dentry;
137 dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
139 if (!rec_dir_init || clp->cl_firststate)
142 status = nfs4_save_creds(&original_cred);
146 /* lock the parent */
147 mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
149 dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1);
150 if (IS_ERR(dentry)) {
151 status = PTR_ERR(dentry);
155 if (dentry->d_inode) {
156 dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
159 status = mnt_want_write(rec_dir.mnt);
162 status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
163 mnt_drop_write(rec_dir.mnt);
167 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
169 clp->cl_firststate = 1;
170 nfsd4_sync_rec_dir();
172 nfs4_reset_creds(original_cred);
173 dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
177 typedef int (recdir_func)(struct dentry *, struct dentry *);
180 char name[HEXDIR_LEN];
181 struct list_head list;
185 nfsd4_build_namelist(void *arg, const char *name, int namlen,
186 loff_t offset, u64 ino, unsigned int d_type)
188 struct list_head *names = arg;
189 struct name_list *entry;
191 if (namlen != HEXDIR_LEN - 1)
193 entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
196 memcpy(entry->name, name, HEXDIR_LEN - 1);
197 entry->name[HEXDIR_LEN - 1] = '\0';
198 list_add(&entry->list, names);
203 nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f)
205 const struct cred *original_cred;
208 struct name_list *entry;
209 struct dentry *dentry;
215 status = nfs4_save_creds(&original_cred);
219 filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
221 status = PTR_ERR(filp);
224 status = vfs_readdir(filp, nfsd4_build_namelist, &names);
226 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
227 while (!list_empty(&names)) {
228 entry = list_entry(names.next, struct name_list, list);
230 dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
231 if (IS_ERR(dentry)) {
232 status = PTR_ERR(dentry);
235 status = f(dir, dentry);
239 list_del(&entry->list);
242 mutex_unlock(&dir->d_inode->i_mutex);
244 while (!list_empty(&names)) {
245 entry = list_entry(names.next, struct name_list, list);
246 list_del(&entry->list);
249 nfs4_reset_creds(original_cred);
254 nfsd4_unlink_clid_dir(char *name, int namlen)
256 struct dentry *dentry;
259 dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
261 mutex_lock_nested(&rec_dir.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
262 dentry = lookup_one_len(name, rec_dir.dentry, namlen);
263 if (IS_ERR(dentry)) {
264 status = PTR_ERR(dentry);
268 if (!dentry->d_inode)
270 status = vfs_rmdir(rec_dir.dentry->d_inode, dentry);
274 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
279 nfsd4_remove_clid_dir(struct nfs4_client *clp)
281 const struct cred *original_cred;
284 if (!rec_dir_init || !clp->cl_firststate)
287 status = mnt_want_write(rec_dir.mnt);
290 clp->cl_firststate = 0;
292 status = nfs4_save_creds(&original_cred);
296 status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
297 nfs4_reset_creds(original_cred);
299 nfsd4_sync_rec_dir();
300 mnt_drop_write(rec_dir.mnt);
303 printk("NFSD: Failed to remove expired client state directory"
304 " %.*s\n", HEXDIR_LEN, clp->cl_recdir);
309 purge_old(struct dentry *parent, struct dentry *child)
313 /* note: we currently use this path only for minorversion 0 */
314 if (nfs4_has_reclaimed_state(child->d_name.name, false))
317 status = vfs_rmdir(parent->d_inode, child);
319 printk("failed to remove client recovery directory %s\n",
321 /* Keep trying, success or failure: */
326 nfsd4_recdir_purge_old(void) {
331 status = mnt_want_write(rec_dir.mnt);
334 status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
336 nfsd4_sync_rec_dir();
337 mnt_drop_write(rec_dir.mnt);
340 printk("nfsd4: failed to purge old clients from recovery"
341 " directory %s\n", rec_dir.dentry->d_name.name);
345 load_recdir(struct dentry *parent, struct dentry *child)
347 if (child->d_name.len != HEXDIR_LEN - 1) {
348 printk("nfsd4: illegal name %s in recovery directory\n",
350 /* Keep trying; maybe the others are OK: */
353 nfs4_client_to_reclaim(child->d_name.name);
358 nfsd4_recdir_load(void) {
361 status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
363 printk("nfsd4: failed loading clients from recovery"
364 " directory %s\n", rec_dir.dentry->d_name.name);
369 * Hold reference to the recovery directory.
373 nfsd4_init_recdir(char *rec_dirname)
375 const struct cred *original_cred;
378 printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
381 BUG_ON(rec_dir_init);
383 status = nfs4_save_creds(&original_cred);
385 printk("NFSD: Unable to change credentials to find recovery"
386 " directory: error %d\n",
391 status = kern_path(rec_dirname, LOOKUP_FOLLOW | LOOKUP_DIRECTORY,
394 printk("NFSD: unable to find recovery directory %s\n",
399 nfs4_reset_creds(original_cred);
403 nfsd4_shutdown_recdir(void)