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/err.h>
37 #include <linux/sunrpc/svc.h>
38 #include <linux/nfsd/nfsd.h>
39 #include <linux/nfs4.h>
40 #include <linux/nfsd/state.h>
41 #include <linux/nfsd/xdr4.h>
42 #include <linux/param.h>
43 #include <linux/file.h>
44 #include <linux/namei.h>
45 #include <asm/uaccess.h>
46 #include <linux/scatterlist.h>
47 #include <linux/crypto.h>
48 #include <linux/sched.h>
49 #include <linux/mount.h>
51 #define NFSDDBG_FACILITY NFSDDBG_PROC
54 static struct nameidata rec_dir;
55 static int rec_dir_init = 0;
58 nfs4_save_user(uid_t *saveuid, gid_t *savegid)
60 *saveuid = current->fsuid;
61 *savegid = current->fsgid;
67 nfs4_reset_user(uid_t saveuid, gid_t savegid)
69 current->fsuid = saveuid;
70 current->fsgid = savegid;
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.path.dentry->d_inode->i_mutex);
125 nfsd_sync_dir(rec_dir.path.dentry);
126 mutex_unlock(&rec_dir.path.dentry->d_inode->i_mutex);
130 nfsd4_create_clid_dir(struct nfs4_client *clp)
132 char *dname = clp->cl_recdir;
133 struct dentry *dentry;
138 dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
140 if (!rec_dir_init || clp->cl_firststate)
143 nfs4_save_user(&uid, &gid);
145 /* lock the parent */
146 mutex_lock(&rec_dir.path.dentry->d_inode->i_mutex);
148 dentry = lookup_one_len(dname, rec_dir.path.dentry, HEXDIR_LEN-1);
149 if (IS_ERR(dentry)) {
150 status = PTR_ERR(dentry);
154 if (dentry->d_inode) {
155 dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
158 status = vfs_mkdir(rec_dir.path.dentry->d_inode, dentry, S_IRWXU);
162 mutex_unlock(&rec_dir.path.dentry->d_inode->i_mutex);
164 clp->cl_firststate = 1;
165 nfsd4_sync_rec_dir();
167 nfs4_reset_user(uid, gid);
168 dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
172 typedef int (recdir_func)(struct dentry *, struct dentry *);
175 struct dentry *dentry;
176 struct list_head list;
179 struct dentry_list_arg {
180 struct list_head dentries;
181 struct dentry *parent;
185 nfsd4_build_dentrylist(void *arg, const char *name, int namlen,
186 loff_t offset, u64 ino, unsigned int d_type)
188 struct dentry_list_arg *dla = arg;
189 struct list_head *dentries = &dla->dentries;
190 struct dentry *parent = dla->parent;
191 struct dentry *dentry;
192 struct dentry_list *child;
194 if (name && isdotent(name, namlen))
196 dentry = lookup_one_len(name, parent, namlen);
198 return PTR_ERR(dentry);
199 child = kmalloc(sizeof(*child), GFP_KERNEL);
202 child->dentry = dentry;
203 list_add(&child->list, dentries);
208 nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f)
211 struct dentry_list_arg dla = {
214 struct list_head *dentries = &dla.dentries;
215 struct dentry_list *child;
223 nfs4_save_user(&uid, &gid);
225 filp = dentry_open(dget(dir), mntget(rec_dir.path.mnt), O_RDONLY);
226 status = PTR_ERR(filp);
229 INIT_LIST_HEAD(dentries);
230 status = vfs_readdir(filp, nfsd4_build_dentrylist, &dla);
232 while (!list_empty(dentries)) {
233 child = list_entry(dentries->next, struct dentry_list, list);
234 status = f(dir, child->dentry);
237 list_del(&child->list);
242 while (!list_empty(dentries)) {
243 child = list_entry(dentries->next, struct dentry_list, list);
244 list_del(&child->list);
248 nfs4_reset_user(uid, gid);
253 nfsd4_remove_clid_file(struct dentry *dir, struct dentry *dentry)
257 if (!S_ISREG(dir->d_inode->i_mode)) {
258 printk("nfsd4: non-file found in client recovery directory\n");
261 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
262 status = vfs_unlink(dir->d_inode, dentry);
263 mutex_unlock(&dir->d_inode->i_mutex);
268 nfsd4_clear_clid_dir(struct dentry *dir, struct dentry *dentry)
272 /* For now this directory should already be empty, but we empty it of
273 * any regular files anyway, just in case the directory was created by
274 * a kernel from the future.... */
275 nfsd4_list_rec_dir(dentry, nfsd4_remove_clid_file);
276 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
277 status = vfs_rmdir(dir->d_inode, dentry);
278 mutex_unlock(&dir->d_inode->i_mutex);
283 nfsd4_unlink_clid_dir(char *name, int namlen)
285 struct dentry *dentry;
288 dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
290 mutex_lock(&rec_dir.path.dentry->d_inode->i_mutex);
291 dentry = lookup_one_len(name, rec_dir.path.dentry, namlen);
292 mutex_unlock(&rec_dir.path.dentry->d_inode->i_mutex);
293 if (IS_ERR(dentry)) {
294 status = PTR_ERR(dentry);
298 if (!dentry->d_inode)
301 status = nfsd4_clear_clid_dir(rec_dir.path.dentry, dentry);
308 nfsd4_remove_clid_dir(struct nfs4_client *clp)
314 if (!rec_dir_init || !clp->cl_firststate)
317 status = mnt_want_write(rec_dir.path.mnt);
320 clp->cl_firststate = 0;
321 nfs4_save_user(&uid, &gid);
322 status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
323 nfs4_reset_user(uid, gid);
325 nfsd4_sync_rec_dir();
326 mnt_drop_write(rec_dir.path.mnt);
329 printk("NFSD: Failed to remove expired client state directory"
330 " %.*s\n", HEXDIR_LEN, clp->cl_recdir);
335 purge_old(struct dentry *parent, struct dentry *child)
339 if (nfs4_has_reclaimed_state(child->d_name.name))
342 status = nfsd4_clear_clid_dir(parent, child);
344 printk("failed to remove client recovery directory %s\n",
346 /* Keep trying, success or failure: */
351 nfsd4_recdir_purge_old(void) {
356 status = mnt_want_write(rec_dir.path.mnt);
359 status = nfsd4_list_rec_dir(rec_dir.path.dentry, purge_old);
361 nfsd4_sync_rec_dir();
362 mnt_drop_write(rec_dir.path.mnt);
365 printk("nfsd4: failed to purge old clients from recovery"
366 " directory %s\n", rec_dir.path.dentry->d_name.name);
370 load_recdir(struct dentry *parent, struct dentry *child)
372 if (child->d_name.len != HEXDIR_LEN - 1) {
373 printk("nfsd4: illegal name %s in recovery directory\n",
375 /* Keep trying; maybe the others are OK: */
378 nfs4_client_to_reclaim(child->d_name.name);
383 nfsd4_recdir_load(void) {
386 status = nfsd4_list_rec_dir(rec_dir.path.dentry, load_recdir);
388 printk("nfsd4: failed loading clients from recovery"
389 " directory %s\n", rec_dir.path.dentry->d_name.name);
394 * Hold reference to the recovery directory.
398 nfsd4_init_recdir(char *rec_dirname)
404 printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
407 BUG_ON(rec_dir_init);
409 nfs4_save_user(&uid, &gid);
411 status = path_lookup(rec_dirname, LOOKUP_FOLLOW | LOOKUP_DIRECTORY,
414 printk("NFSD: unable to find recovery directory %s\n",
419 nfs4_reset_user(uid, gid);
423 nfsd4_shutdown_recdir(void)
428 path_put(&rec_dir.path);