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 path rec_dir;
55 static int rec_dir_init = 0;
58 nfs4_save_user(uid_t *saveuid, gid_t *savegid)
60 *saveuid = current->cred->fsuid;
61 *savegid = current->cred->fsgid;
62 current->cred->fsuid = 0;
63 current->cred->fsgid = 0;
67 nfs4_reset_user(uid_t saveuid, gid_t savegid)
69 current->cred->fsuid = saveuid;
70 current->cred->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.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 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.dentry->d_inode->i_mutex);
148 dentry = lookup_one_len(dname, rec_dir.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 = mnt_want_write(rec_dir.mnt);
161 status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
162 mnt_drop_write(rec_dir.mnt);
166 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
168 clp->cl_firststate = 1;
169 nfsd4_sync_rec_dir();
171 nfs4_reset_user(uid, gid);
172 dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
176 typedef int (recdir_func)(struct dentry *, struct dentry *);
179 struct dentry *dentry;
180 struct list_head list;
183 struct dentry_list_arg {
184 struct list_head dentries;
185 struct dentry *parent;
189 nfsd4_build_dentrylist(void *arg, const char *name, int namlen,
190 loff_t offset, u64 ino, unsigned int d_type)
192 struct dentry_list_arg *dla = arg;
193 struct list_head *dentries = &dla->dentries;
194 struct dentry *parent = dla->parent;
195 struct dentry *dentry;
196 struct dentry_list *child;
198 if (name && isdotent(name, namlen))
200 dentry = lookup_one_len(name, parent, namlen);
202 return PTR_ERR(dentry);
203 child = kmalloc(sizeof(*child), GFP_KERNEL);
206 child->dentry = dentry;
207 list_add(&child->list, dentries);
212 nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f)
215 struct dentry_list_arg dla = {
218 struct list_head *dentries = &dla.dentries;
219 struct dentry_list *child;
227 nfs4_save_user(&uid, &gid);
229 filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
231 status = PTR_ERR(filp);
234 INIT_LIST_HEAD(dentries);
235 status = vfs_readdir(filp, nfsd4_build_dentrylist, &dla);
237 while (!list_empty(dentries)) {
238 child = list_entry(dentries->next, struct dentry_list, list);
239 status = f(dir, child->dentry);
242 list_del(&child->list);
247 while (!list_empty(dentries)) {
248 child = list_entry(dentries->next, struct dentry_list, list);
249 list_del(&child->list);
253 nfs4_reset_user(uid, gid);
258 nfsd4_remove_clid_file(struct dentry *dir, struct dentry *dentry)
262 if (!S_ISREG(dir->d_inode->i_mode)) {
263 printk("nfsd4: non-file found in client recovery directory\n");
266 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
267 status = vfs_unlink(dir->d_inode, dentry);
268 mutex_unlock(&dir->d_inode->i_mutex);
273 nfsd4_clear_clid_dir(struct dentry *dir, struct dentry *dentry)
277 /* For now this directory should already be empty, but we empty it of
278 * any regular files anyway, just in case the directory was created by
279 * a kernel from the future.... */
280 nfsd4_list_rec_dir(dentry, nfsd4_remove_clid_file);
281 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
282 status = vfs_rmdir(dir->d_inode, dentry);
283 mutex_unlock(&dir->d_inode->i_mutex);
288 nfsd4_unlink_clid_dir(char *name, int namlen)
290 struct dentry *dentry;
293 dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
295 mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
296 dentry = lookup_one_len(name, rec_dir.dentry, namlen);
297 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
298 if (IS_ERR(dentry)) {
299 status = PTR_ERR(dentry);
303 if (!dentry->d_inode)
306 status = nfsd4_clear_clid_dir(rec_dir.dentry, dentry);
313 nfsd4_remove_clid_dir(struct nfs4_client *clp)
319 if (!rec_dir_init || !clp->cl_firststate)
322 status = mnt_want_write(rec_dir.mnt);
325 clp->cl_firststate = 0;
326 nfs4_save_user(&uid, &gid);
327 status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
328 nfs4_reset_user(uid, gid);
330 nfsd4_sync_rec_dir();
331 mnt_drop_write(rec_dir.mnt);
334 printk("NFSD: Failed to remove expired client state directory"
335 " %.*s\n", HEXDIR_LEN, clp->cl_recdir);
340 purge_old(struct dentry *parent, struct dentry *child)
344 if (nfs4_has_reclaimed_state(child->d_name.name))
347 status = nfsd4_clear_clid_dir(parent, child);
349 printk("failed to remove client recovery directory %s\n",
351 /* Keep trying, success or failure: */
356 nfsd4_recdir_purge_old(void) {
361 status = mnt_want_write(rec_dir.mnt);
364 status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
366 nfsd4_sync_rec_dir();
367 mnt_drop_write(rec_dir.mnt);
370 printk("nfsd4: failed to purge old clients from recovery"
371 " directory %s\n", rec_dir.dentry->d_name.name);
375 load_recdir(struct dentry *parent, struct dentry *child)
377 if (child->d_name.len != HEXDIR_LEN - 1) {
378 printk("nfsd4: illegal name %s in recovery directory\n",
380 /* Keep trying; maybe the others are OK: */
383 nfs4_client_to_reclaim(child->d_name.name);
388 nfsd4_recdir_load(void) {
391 status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
393 printk("nfsd4: failed loading clients from recovery"
394 " directory %s\n", rec_dir.dentry->d_name.name);
399 * Hold reference to the recovery directory.
403 nfsd4_init_recdir(char *rec_dirname)
409 printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
412 BUG_ON(rec_dir_init);
414 nfs4_save_user(&uid, &gid);
416 status = kern_path(rec_dirname, LOOKUP_FOLLOW | LOOKUP_DIRECTORY,
419 printk("NFSD: unable to find recovery directory %s\n",
424 nfs4_reset_user(uid, gid);
428 nfsd4_shutdown_recdir(void)