blob: 632a50b4b371064d8a837d71f89d7e645384d359 [file] [log] [blame]
NeilBrowna55370a2005-06-23 22:03:52 -07001/*
2* linux/fs/nfsd/nfs4recover.c
3*
4* Copyright (c) 2004 The Regents of the University of Michigan.
5* All rights reserved.
6*
7* Andy Adamson <andros@citi.umich.edu>
8*
9* Redistribution and use in source and binary forms, with or without
10* modification, are permitted provided that the following conditions
11* are met:
12*
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.
21*
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.
33*
34*/
35
Herbert Xu35058682006-08-24 19:10:20 +100036#include <linux/err.h>
NeilBrowna55370a2005-06-23 22:03:52 -070037#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>
NeilBrown190e4fb2005-06-23 22:04:25 -070042#include <linux/param.h>
43#include <linux/file.h>
44#include <linux/namei.h>
NeilBrowna55370a2005-06-23 22:03:52 -070045#include <asm/uaccess.h>
Adrian Bunk87ae9af2007-10-30 10:35:04 +010046#include <linux/scatterlist.h>
NeilBrowna55370a2005-06-23 22:03:52 -070047#include <linux/crypto.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040048#include <linux/sched.h>
Dave Hansen06227532008-02-15 14:37:34 -080049#include <linux/mount.h>
NeilBrowna55370a2005-06-23 22:03:52 -070050
51#define NFSDDBG_FACILITY NFSDDBG_PROC
52
NeilBrown190e4fb2005-06-23 22:04:25 -070053/* Globals */
Al Viroa63bb992008-08-02 01:03:36 -040054static struct path rec_dir;
NeilBrown190e4fb2005-06-23 22:04:25 -070055static int rec_dir_init = 0;
56
57static void
58nfs4_save_user(uid_t *saveuid, gid_t *savegid)
59{
David Howellsb6dff3e2008-11-14 10:39:16 +110060 *saveuid = current->cred->fsuid;
61 *savegid = current->cred->fsgid;
62 current->cred->fsuid = 0;
63 current->cred->fsgid = 0;
NeilBrown190e4fb2005-06-23 22:04:25 -070064}
65
66static void
67nfs4_reset_user(uid_t saveuid, gid_t savegid)
68{
David Howellsb6dff3e2008-11-14 10:39:16 +110069 current->cred->fsuid = saveuid;
70 current->cred->fsgid = savegid;
NeilBrown190e4fb2005-06-23 22:04:25 -070071}
72
NeilBrowna55370a2005-06-23 22:03:52 -070073static void
74md5_to_hex(char *out, char *md5)
75{
76 int i;
77
78 for (i=0; i<16; i++) {
79 unsigned char c = md5[i];
80
81 *out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
82 *out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
83 }
84 *out = '\0';
85}
86
Al Virob37ad282006-10-19 23:28:59 -070087__be32
NeilBrowna55370a2005-06-23 22:03:52 -070088nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname)
89{
90 struct xdr_netobj cksum;
Herbert Xu35058682006-08-24 19:10:20 +100091 struct hash_desc desc;
Jens Axboe60c74f82007-10-22 19:43:30 +020092 struct scatterlist sg;
Al Virob37ad282006-10-19 23:28:59 -070093 __be32 status = nfserr_resource;
NeilBrowna55370a2005-06-23 22:03:52 -070094
95 dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
96 clname->len, clname->data);
Herbert Xu35058682006-08-24 19:10:20 +100097 desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
98 desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
99 if (IS_ERR(desc.tfm))
100 goto out_no_tfm;
101 cksum.len = crypto_hash_digestsize(desc.tfm);
NeilBrowna55370a2005-06-23 22:03:52 -0700102 cksum.data = kmalloc(cksum.len, GFP_KERNEL);
103 if (cksum.data == NULL)
104 goto out;
NeilBrowna55370a2005-06-23 22:03:52 -0700105
Jens Axboe60c74f82007-10-22 19:43:30 +0200106 sg_init_one(&sg, clname->data, clname->len);
NeilBrowna55370a2005-06-23 22:03:52 -0700107
Jens Axboe60c74f82007-10-22 19:43:30 +0200108 if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
Herbert Xu35058682006-08-24 19:10:20 +1000109 goto out;
NeilBrowna55370a2005-06-23 22:03:52 -0700110
111 md5_to_hex(dname, cksum.data);
112
113 kfree(cksum.data);
114 status = nfs_ok;
115out:
Herbert Xu35058682006-08-24 19:10:20 +1000116 crypto_free_hash(desc.tfm);
117out_no_tfm:
NeilBrowna55370a2005-06-23 22:03:52 -0700118 return status;
119}
NeilBrown190e4fb2005-06-23 22:04:25 -0700120
NeilBrowna6ccbbb2005-07-07 17:59:11 -0700121static void
122nfsd4_sync_rec_dir(void)
NeilBrownc7b9a452005-06-23 22:04:30 -0700123{
Al Viroa63bb992008-08-02 01:03:36 -0400124 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);
NeilBrownc7b9a452005-06-23 22:04:30 -0700127}
128
129int
130nfsd4_create_clid_dir(struct nfs4_client *clp)
131{
132 char *dname = clp->cl_recdir;
133 struct dentry *dentry;
134 uid_t uid;
135 gid_t gid;
136 int status;
137
138 dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
139
140 if (!rec_dir_init || clp->cl_firststate)
141 return 0;
142
143 nfs4_save_user(&uid, &gid);
144
145 /* lock the parent */
Al Viroa63bb992008-08-02 01:03:36 -0400146 mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
NeilBrownc7b9a452005-06-23 22:04:30 -0700147
Al Viroa63bb992008-08-02 01:03:36 -0400148 dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1);
NeilBrownc7b9a452005-06-23 22:04:30 -0700149 if (IS_ERR(dentry)) {
150 status = PTR_ERR(dentry);
151 goto out_unlock;
152 }
153 status = -EEXIST;
154 if (dentry->d_inode) {
155 dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
156 goto out_put;
157 }
Al Viroa63bb992008-08-02 01:03:36 -0400158 status = mnt_want_write(rec_dir.mnt);
Dave Hansen463c3192008-02-15 14:37:57 -0800159 if (status)
160 goto out_put;
Al Viroa63bb992008-08-02 01:03:36 -0400161 status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
162 mnt_drop_write(rec_dir.mnt);
NeilBrownc7b9a452005-06-23 22:04:30 -0700163out_put:
164 dput(dentry);
165out_unlock:
Al Viroa63bb992008-08-02 01:03:36 -0400166 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
NeilBrownc7b9a452005-06-23 22:04:30 -0700167 if (status == 0) {
168 clp->cl_firststate = 1;
NeilBrowna6ccbbb2005-07-07 17:59:11 -0700169 nfsd4_sync_rec_dir();
NeilBrownc7b9a452005-06-23 22:04:30 -0700170 }
171 nfs4_reset_user(uid, gid);
172 dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
173 return status;
174}
175
NeilBrown190e4fb2005-06-23 22:04:25 -0700176typedef int (recdir_func)(struct dentry *, struct dentry *);
177
178struct dentry_list {
179 struct dentry *dentry;
180 struct list_head list;
181};
182
183struct dentry_list_arg {
184 struct list_head dentries;
185 struct dentry *parent;
186};
187
188static int
189nfsd4_build_dentrylist(void *arg, const char *name, int namlen,
David Howellsafefdbb2006-10-03 01:13:46 -0700190 loff_t offset, u64 ino, unsigned int d_type)
NeilBrown190e4fb2005-06-23 22:04:25 -0700191{
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;
197
198 if (name && isdotent(name, namlen))
Al Virob37ad282006-10-19 23:28:59 -0700199 return 0;
NeilBrown190e4fb2005-06-23 22:04:25 -0700200 dentry = lookup_one_len(name, parent, namlen);
201 if (IS_ERR(dentry))
202 return PTR_ERR(dentry);
203 child = kmalloc(sizeof(*child), GFP_KERNEL);
204 if (child == NULL)
205 return -ENOMEM;
206 child->dentry = dentry;
207 list_add(&child->list, dentries);
208 return 0;
209}
210
211static int
212nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f)
213{
214 struct file *filp;
215 struct dentry_list_arg dla = {
216 .parent = dir,
217 };
218 struct list_head *dentries = &dla.dentries;
219 struct dentry_list *child;
220 uid_t uid;
221 gid_t gid;
222 int status;
223
224 if (!rec_dir_init)
225 return 0;
226
227 nfs4_save_user(&uid, &gid);
228
David Howells745ca242008-11-14 10:39:22 +1100229 filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
230 current_cred());
NeilBrown190e4fb2005-06-23 22:04:25 -0700231 status = PTR_ERR(filp);
232 if (IS_ERR(filp))
233 goto out;
234 INIT_LIST_HEAD(dentries);
235 status = vfs_readdir(filp, nfsd4_build_dentrylist, &dla);
236 fput(filp);
237 while (!list_empty(dentries)) {
238 child = list_entry(dentries->next, struct dentry_list, list);
239 status = f(dir, child->dentry);
240 if (status)
241 goto out;
242 list_del(&child->list);
243 dput(child->dentry);
244 kfree(child);
245 }
246out:
247 while (!list_empty(dentries)) {
248 child = list_entry(dentries->next, struct dentry_list, list);
249 list_del(&child->list);
250 dput(child->dentry);
251 kfree(child);
252 }
253 nfs4_reset_user(uid, gid);
254 return status;
255}
256
257static int
NeilBrownc7b9a452005-06-23 22:04:30 -0700258nfsd4_remove_clid_file(struct dentry *dir, struct dentry *dentry)
259{
260 int status;
261
262 if (!S_ISREG(dir->d_inode->i_mode)) {
263 printk("nfsd4: non-file found in client recovery directory\n");
264 return -EINVAL;
265 }
Peter Zijlstra4b75f782006-12-08 02:39:38 -0800266 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
NeilBrownc7b9a452005-06-23 22:04:30 -0700267 status = vfs_unlink(dir->d_inode, dentry);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800268 mutex_unlock(&dir->d_inode->i_mutex);
NeilBrownc7b9a452005-06-23 22:04:30 -0700269 return status;
270}
271
272static int
273nfsd4_clear_clid_dir(struct dentry *dir, struct dentry *dentry)
274{
275 int status;
276
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);
Srinivasa Ds7ef55b82006-11-02 22:07:12 -0800281 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
NeilBrownc7b9a452005-06-23 22:04:30 -0700282 status = vfs_rmdir(dir->d_inode, dentry);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800283 mutex_unlock(&dir->d_inode->i_mutex);
NeilBrownc7b9a452005-06-23 22:04:30 -0700284 return status;
285}
286
287static int
288nfsd4_unlink_clid_dir(char *name, int namlen)
289{
290 struct dentry *dentry;
291 int status;
292
293 dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
294
Al Viroa63bb992008-08-02 01:03:36 -0400295 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);
NeilBrownc7b9a452005-06-23 22:04:30 -0700298 if (IS_ERR(dentry)) {
299 status = PTR_ERR(dentry);
300 return status;
301 }
302 status = -ENOENT;
303 if (!dentry->d_inode)
304 goto out;
305
Al Viroa63bb992008-08-02 01:03:36 -0400306 status = nfsd4_clear_clid_dir(rec_dir.dentry, dentry);
NeilBrownc7b9a452005-06-23 22:04:30 -0700307out:
308 dput(dentry);
309 return status;
310}
311
312void
313nfsd4_remove_clid_dir(struct nfs4_client *clp)
314{
315 uid_t uid;
316 gid_t gid;
317 int status;
318
319 if (!rec_dir_init || !clp->cl_firststate)
320 return;
321
Al Viroa63bb992008-08-02 01:03:36 -0400322 status = mnt_want_write(rec_dir.mnt);
Dave Hansen06227532008-02-15 14:37:34 -0800323 if (status)
324 goto out;
NeilBrown67be4312005-07-07 17:59:13 -0700325 clp->cl_firststate = 0;
NeilBrownc7b9a452005-06-23 22:04:30 -0700326 nfs4_save_user(&uid, &gid);
327 status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
328 nfs4_reset_user(uid, gid);
329 if (status == 0)
NeilBrowna6ccbbb2005-07-07 17:59:11 -0700330 nfsd4_sync_rec_dir();
Al Viroa63bb992008-08-02 01:03:36 -0400331 mnt_drop_write(rec_dir.mnt);
Dave Hansen06227532008-02-15 14:37:34 -0800332out:
NeilBrownc7b9a452005-06-23 22:04:30 -0700333 if (status)
334 printk("NFSD: Failed to remove expired client state directory"
335 " %.*s\n", HEXDIR_LEN, clp->cl_recdir);
336 return;
337}
338
339static int
340purge_old(struct dentry *parent, struct dentry *child)
341{
342 int status;
343
344 if (nfs4_has_reclaimed_state(child->d_name.name))
Al Virob37ad282006-10-19 23:28:59 -0700345 return 0;
NeilBrownc7b9a452005-06-23 22:04:30 -0700346
347 status = nfsd4_clear_clid_dir(parent, child);
348 if (status)
349 printk("failed to remove client recovery directory %s\n",
350 child->d_name.name);
351 /* Keep trying, success or failure: */
Al Virob37ad282006-10-19 23:28:59 -0700352 return 0;
NeilBrownc7b9a452005-06-23 22:04:30 -0700353}
354
355void
356nfsd4_recdir_purge_old(void) {
357 int status;
358
359 if (!rec_dir_init)
360 return;
Al Viroa63bb992008-08-02 01:03:36 -0400361 status = mnt_want_write(rec_dir.mnt);
Dave Hansen06227532008-02-15 14:37:34 -0800362 if (status)
363 goto out;
Al Viroa63bb992008-08-02 01:03:36 -0400364 status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
NeilBrownc7b9a452005-06-23 22:04:30 -0700365 if (status == 0)
NeilBrowna6ccbbb2005-07-07 17:59:11 -0700366 nfsd4_sync_rec_dir();
Al Viroa63bb992008-08-02 01:03:36 -0400367 mnt_drop_write(rec_dir.mnt);
Dave Hansen06227532008-02-15 14:37:34 -0800368out:
NeilBrownc7b9a452005-06-23 22:04:30 -0700369 if (status)
370 printk("nfsd4: failed to purge old clients from recovery"
Al Viroa63bb992008-08-02 01:03:36 -0400371 " directory %s\n", rec_dir.dentry->d_name.name);
NeilBrownc7b9a452005-06-23 22:04:30 -0700372}
373
374static int
NeilBrown190e4fb2005-06-23 22:04:25 -0700375load_recdir(struct dentry *parent, struct dentry *child)
376{
377 if (child->d_name.len != HEXDIR_LEN - 1) {
378 printk("nfsd4: illegal name %s in recovery directory\n",
379 child->d_name.name);
380 /* Keep trying; maybe the others are OK: */
Al Virob37ad282006-10-19 23:28:59 -0700381 return 0;
NeilBrown190e4fb2005-06-23 22:04:25 -0700382 }
383 nfs4_client_to_reclaim(child->d_name.name);
Al Virob37ad282006-10-19 23:28:59 -0700384 return 0;
NeilBrown190e4fb2005-06-23 22:04:25 -0700385}
386
387int
388nfsd4_recdir_load(void) {
389 int status;
390
Al Viroa63bb992008-08-02 01:03:36 -0400391 status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
NeilBrown190e4fb2005-06-23 22:04:25 -0700392 if (status)
393 printk("nfsd4: failed loading clients from recovery"
Al Viroa63bb992008-08-02 01:03:36 -0400394 " directory %s\n", rec_dir.dentry->d_name.name);
NeilBrown190e4fb2005-06-23 22:04:25 -0700395 return status;
396}
397
398/*
399 * Hold reference to the recovery directory.
400 */
401
402void
403nfsd4_init_recdir(char *rec_dirname)
404{
405 uid_t uid = 0;
406 gid_t gid = 0;
407 int status;
408
409 printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
410 rec_dirname);
411
412 BUG_ON(rec_dir_init);
413
414 nfs4_save_user(&uid, &gid);
415
Al Viroa63bb992008-08-02 01:03:36 -0400416 status = kern_path(rec_dirname, LOOKUP_FOLLOW | LOOKUP_DIRECTORY,
J. Bruce Fieldsc2642ab2006-01-18 17:43:29 -0800417 &rec_dir);
418 if (status)
419 printk("NFSD: unable to find recovery directory %s\n",
NeilBrown190e4fb2005-06-23 22:04:25 -0700420 rec_dirname);
421
422 if (!status)
423 rec_dir_init = 1;
424 nfs4_reset_user(uid, gid);
425}
426
427void
428nfsd4_shutdown_recdir(void)
429{
430 if (!rec_dir_init)
431 return;
432 rec_dir_init = 0;
Al Viroa63bb992008-08-02 01:03:36 -0400433 path_put(&rec_dir);
NeilBrown190e4fb2005-06-23 22:04:25 -0700434}