QE/FHCI: fixed the CONTROL bug
[zen-stable.git] / fs / nfsd / nfs4recover.c
blob29d77f60585bc17713c8ccfc12b9c8f7aff4b14f
1 /*
2 * Copyright (c) 2004 The Regents of the University of Michigan.
3 * All rights reserved.
5 * Andy Adamson <andros@citi.umich.edu>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its
17 * contributors may be used to endorse or promote products derived
18 * from this software without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
21 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
22 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
23 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
27 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 #include <linux/file.h>
35 #include <linux/slab.h>
36 #include <linux/namei.h>
37 #include <linux/crypto.h>
38 #include <linux/sched.h>
40 #include "nfsd.h"
41 #include "state.h"
42 #include "vfs.h"
44 #define NFSDDBG_FACILITY NFSDDBG_PROC
46 /* Globals */
47 static struct file *rec_file;
49 static int
50 nfs4_save_creds(const struct cred **original_creds)
52 struct cred *new;
54 new = prepare_creds();
55 if (!new)
56 return -ENOMEM;
58 new->fsuid = 0;
59 new->fsgid = 0;
60 *original_creds = override_creds(new);
61 put_cred(new);
62 return 0;
65 static void
66 nfs4_reset_creds(const struct cred *original)
68 revert_creds(original);
71 static void
72 md5_to_hex(char *out, char *md5)
74 int i;
76 for (i=0; i<16; i++) {
77 unsigned char c = md5[i];
79 *out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
80 *out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
82 *out = '\0';
85 __be32
86 nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname)
88 struct xdr_netobj cksum;
89 struct hash_desc desc;
90 struct scatterlist sg;
91 __be32 status = nfserr_resource;
93 dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
94 clname->len, clname->data);
95 desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
96 desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
97 if (IS_ERR(desc.tfm))
98 goto out_no_tfm;
99 cksum.len = crypto_hash_digestsize(desc.tfm);
100 cksum.data = kmalloc(cksum.len, GFP_KERNEL);
101 if (cksum.data == NULL)
102 goto out;
104 sg_init_one(&sg, clname->data, clname->len);
106 if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
107 goto out;
109 md5_to_hex(dname, cksum.data);
111 status = nfs_ok;
112 out:
113 kfree(cksum.data);
114 crypto_free_hash(desc.tfm);
115 out_no_tfm:
116 return status;
120 nfsd4_create_clid_dir(struct nfs4_client *clp)
122 const struct cred *original_cred;
123 char *dname = clp->cl_recdir;
124 struct dentry *dir, *dentry;
125 int status;
127 dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
129 if (!rec_file || clp->cl_firststate)
130 return 0;
132 status = nfs4_save_creds(&original_cred);
133 if (status < 0)
134 return status;
136 dir = rec_file->f_path.dentry;
137 /* lock the parent */
138 mutex_lock(&dir->d_inode->i_mutex);
140 dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1);
141 if (IS_ERR(dentry)) {
142 status = PTR_ERR(dentry);
143 goto out_unlock;
145 status = -EEXIST;
146 if (dentry->d_inode) {
147 dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
148 goto out_put;
150 status = mnt_want_write(rec_file->f_path.mnt);
151 if (status)
152 goto out_put;
153 status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU);
154 mnt_drop_write(rec_file->f_path.mnt);
155 out_put:
156 dput(dentry);
157 out_unlock:
158 mutex_unlock(&dir->d_inode->i_mutex);
159 if (status == 0) {
160 clp->cl_firststate = 1;
161 vfs_fsync(rec_file, 0);
163 nfs4_reset_creds(original_cred);
164 dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
165 return status;
168 typedef int (recdir_func)(struct dentry *, struct dentry *);
170 struct name_list {
171 char name[HEXDIR_LEN];
172 struct list_head list;
175 static int
176 nfsd4_build_namelist(void *arg, const char *name, int namlen,
177 loff_t offset, u64 ino, unsigned int d_type)
179 struct list_head *names = arg;
180 struct name_list *entry;
182 if (namlen != HEXDIR_LEN - 1)
183 return 0;
184 entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
185 if (entry == NULL)
186 return -ENOMEM;
187 memcpy(entry->name, name, HEXDIR_LEN - 1);
188 entry->name[HEXDIR_LEN - 1] = '\0';
189 list_add(&entry->list, names);
190 return 0;
193 static int
194 nfsd4_list_rec_dir(recdir_func *f)
196 const struct cred *original_cred;
197 struct dentry *dir = rec_file->f_path.dentry;
198 LIST_HEAD(names);
199 int status;
201 status = nfs4_save_creds(&original_cred);
202 if (status < 0)
203 return status;
205 status = vfs_llseek(rec_file, 0, SEEK_SET);
206 if (status < 0) {
207 nfs4_reset_creds(original_cred);
208 return status;
211 status = vfs_readdir(rec_file, nfsd4_build_namelist, &names);
212 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
213 while (!list_empty(&names)) {
214 struct name_list *entry;
215 entry = list_entry(names.next, struct name_list, list);
216 if (!status) {
217 struct dentry *dentry;
218 dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
219 if (IS_ERR(dentry)) {
220 status = PTR_ERR(dentry);
221 break;
223 status = f(dir, dentry);
224 dput(dentry);
226 list_del(&entry->list);
227 kfree(entry);
229 mutex_unlock(&dir->d_inode->i_mutex);
230 nfs4_reset_creds(original_cred);
231 return status;
234 static int
235 nfsd4_unlink_clid_dir(char *name, int namlen)
237 struct dentry *dir, *dentry;
238 int status;
240 dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
242 dir = rec_file->f_path.dentry;
243 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
244 dentry = lookup_one_len(name, dir, namlen);
245 if (IS_ERR(dentry)) {
246 status = PTR_ERR(dentry);
247 goto out_unlock;
249 status = -ENOENT;
250 if (!dentry->d_inode)
251 goto out;
252 status = vfs_rmdir(dir->d_inode, dentry);
253 out:
254 dput(dentry);
255 out_unlock:
256 mutex_unlock(&dir->d_inode->i_mutex);
257 return status;
260 void
261 nfsd4_remove_clid_dir(struct nfs4_client *clp)
263 const struct cred *original_cred;
264 int status;
266 if (!rec_file || !clp->cl_firststate)
267 return;
269 status = mnt_want_write(rec_file->f_path.mnt);
270 if (status)
271 goto out;
272 clp->cl_firststate = 0;
274 status = nfs4_save_creds(&original_cred);
275 if (status < 0)
276 goto out;
278 status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
279 nfs4_reset_creds(original_cred);
280 if (status == 0)
281 vfs_fsync(rec_file, 0);
282 mnt_drop_write(rec_file->f_path.mnt);
283 out:
284 if (status)
285 printk("NFSD: Failed to remove expired client state directory"
286 " %.*s\n", HEXDIR_LEN, clp->cl_recdir);
287 return;
290 static int
291 purge_old(struct dentry *parent, struct dentry *child)
293 int status;
295 if (nfs4_has_reclaimed_state(child->d_name.name, false))
296 return 0;
298 status = vfs_rmdir(parent->d_inode, child);
299 if (status)
300 printk("failed to remove client recovery directory %s\n",
301 child->d_name.name);
302 /* Keep trying, success or failure: */
303 return 0;
306 void
307 nfsd4_recdir_purge_old(void) {
308 int status;
310 if (!rec_file)
311 return;
312 status = mnt_want_write(rec_file->f_path.mnt);
313 if (status)
314 goto out;
315 status = nfsd4_list_rec_dir(purge_old);
316 if (status == 0)
317 vfs_fsync(rec_file, 0);
318 mnt_drop_write(rec_file->f_path.mnt);
319 out:
320 if (status)
321 printk("nfsd4: failed to purge old clients from recovery"
322 " directory %s\n", rec_file->f_path.dentry->d_name.name);
325 static int
326 load_recdir(struct dentry *parent, struct dentry *child)
328 if (child->d_name.len != HEXDIR_LEN - 1) {
329 printk("nfsd4: illegal name %s in recovery directory\n",
330 child->d_name.name);
331 /* Keep trying; maybe the others are OK: */
332 return 0;
334 nfs4_client_to_reclaim(child->d_name.name);
335 return 0;
339 nfsd4_recdir_load(void) {
340 int status;
342 if (!rec_file)
343 return 0;
345 status = nfsd4_list_rec_dir(load_recdir);
346 if (status)
347 printk("nfsd4: failed loading clients from recovery"
348 " directory %s\n", rec_file->f_path.dentry->d_name.name);
349 return status;
353 * Hold reference to the recovery directory.
356 void
357 nfsd4_init_recdir(char *rec_dirname)
359 const struct cred *original_cred;
360 int status;
362 printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
363 rec_dirname);
365 BUG_ON(rec_file);
367 status = nfs4_save_creds(&original_cred);
368 if (status < 0) {
369 printk("NFSD: Unable to change credentials to find recovery"
370 " directory: error %d\n",
371 status);
372 return;
375 rec_file = filp_open(rec_dirname, O_RDONLY | O_DIRECTORY, 0);
376 if (IS_ERR(rec_file)) {
377 printk("NFSD: unable to find recovery directory %s\n",
378 rec_dirname);
379 rec_file = NULL;
382 nfs4_reset_creds(original_cred);
385 void
386 nfsd4_shutdown_recdir(void)
388 if (!rec_file)
389 return;
390 fput(rec_file);
391 rec_file = NULL;