Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ecryptfs...
[pandora-kernel.git] / fs / ecryptfs / inode.c
1 /**
2  * eCryptfs: Linux filesystem encryption layer
3  *
4  * Copyright (C) 1997-2004 Erez Zadok
5  * Copyright (C) 2001-2004 Stony Brook University
6  * Copyright (C) 2004-2007 International Business Machines Corp.
7  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
8  *              Michael C. Thompsion <mcthomps@us.ibm.com>
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 of the
13  * License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful, but
16  * WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
23  * 02111-1307, USA.
24  */
25
26 #include <linux/file.h>
27 #include <linux/vmalloc.h>
28 #include <linux/pagemap.h>
29 #include <linux/dcache.h>
30 #include <linux/namei.h>
31 #include <linux/mount.h>
32 #include <linux/crypto.h>
33 #include <linux/fs_stack.h>
34 #include <linux/slab.h>
35 #include <asm/unaligned.h>
36 #include "ecryptfs_kernel.h"
37
38 static struct dentry *lock_parent(struct dentry *dentry)
39 {
40         struct dentry *dir;
41
42         dir = dget_parent(dentry);
43         mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT);
44         return dir;
45 }
46
47 static void unlock_dir(struct dentry *dir)
48 {
49         mutex_unlock(&dir->d_inode->i_mutex);
50         dput(dir);
51 }
52
53 /**
54  * ecryptfs_create_underlying_file
55  * @lower_dir_inode: inode of the parent in the lower fs of the new file
56  * @dentry: New file's dentry
57  * @mode: The mode of the new file
58  * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
59  *
60  * Creates the file in the lower file system.
61  *
62  * Returns zero on success; non-zero on error condition
63  */
64 static int
65 ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
66                                 struct dentry *dentry, int mode,
67                                 struct nameidata *nd)
68 {
69         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
70         struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
71         struct dentry *dentry_save;
72         struct vfsmount *vfsmount_save;
73         int rc;
74
75         dentry_save = nd->path.dentry;
76         vfsmount_save = nd->path.mnt;
77         nd->path.dentry = lower_dentry;
78         nd->path.mnt = lower_mnt;
79         rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
80         nd->path.dentry = dentry_save;
81         nd->path.mnt = vfsmount_save;
82         return rc;
83 }
84
85 /**
86  * ecryptfs_do_create
87  * @directory_inode: inode of the new file's dentry's parent in ecryptfs
88  * @ecryptfs_dentry: New file's dentry in ecryptfs
89  * @mode: The mode of the new file
90  * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
91  *
92  * Creates the underlying file and the eCryptfs inode which will link to
93  * it. It will also update the eCryptfs directory inode to mimic the
94  * stat of the lower directory inode.
95  *
96  * Returns zero on success; non-zero on error condition
97  */
98 static int
99 ecryptfs_do_create(struct inode *directory_inode,
100                    struct dentry *ecryptfs_dentry, int mode,
101                    struct nameidata *nd)
102 {
103         int rc;
104         struct dentry *lower_dentry;
105         struct dentry *lower_dir_dentry;
106
107         lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
108         lower_dir_dentry = lock_parent(lower_dentry);
109         if (IS_ERR(lower_dir_dentry)) {
110                 ecryptfs_printk(KERN_ERR, "Error locking directory of "
111                                 "dentry\n");
112                 rc = PTR_ERR(lower_dir_dentry);
113                 goto out;
114         }
115         rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
116                                              ecryptfs_dentry, mode, nd);
117         if (rc) {
118                 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
119                        "rc = [%d]\n", __func__, rc);
120                 goto out_lock;
121         }
122         rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
123                                 directory_inode->i_sb, 0);
124         if (rc) {
125                 ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
126                 goto out_lock;
127         }
128         fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
129         fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
130 out_lock:
131         unlock_dir(lower_dir_dentry);
132 out:
133         return rc;
134 }
135
136 /**
137  * grow_file
138  * @ecryptfs_dentry: the eCryptfs dentry
139  *
140  * This is the code which will grow the file to its correct size.
141  */
142 static int grow_file(struct dentry *ecryptfs_dentry)
143 {
144         struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
145         struct file fake_file;
146         struct ecryptfs_file_info tmp_file_info;
147         char zero_virt[] = { 0x00 };
148         int rc = 0;
149
150         memset(&fake_file, 0, sizeof(fake_file));
151         fake_file.f_path.dentry = ecryptfs_dentry;
152         memset(&tmp_file_info, 0, sizeof(tmp_file_info));
153         ecryptfs_set_file_private(&fake_file, &tmp_file_info);
154         ecryptfs_set_file_lower(
155                 &fake_file,
156                 ecryptfs_inode_to_private(ecryptfs_inode)->lower_file);
157         rc = ecryptfs_write(&fake_file, zero_virt, 0, 1);
158         i_size_write(ecryptfs_inode, 0);
159         rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
160         ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |=
161                 ECRYPTFS_NEW_FILE;
162         return rc;
163 }
164
165 /**
166  * ecryptfs_initialize_file
167  *
168  * Cause the file to be changed from a basic empty file to an ecryptfs
169  * file with a header and first data page.
170  *
171  * Returns zero on success
172  */
173 static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
174 {
175         struct ecryptfs_crypt_stat *crypt_stat =
176                 &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
177         int rc = 0;
178
179         if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
180                 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
181                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
182                 goto out;
183         }
184         crypt_stat->flags |= ECRYPTFS_NEW_FILE;
185         ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
186         rc = ecryptfs_new_file_context(ecryptfs_dentry);
187         if (rc) {
188                 ecryptfs_printk(KERN_ERR, "Error creating new file "
189                                 "context; rc = [%d]\n", rc);
190                 goto out;
191         }
192         if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
193                 rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
194                 if (rc) {
195                         printk(KERN_ERR "%s: Error attempting to initialize "
196                                "the persistent file for the dentry with name "
197                                "[%s]; rc = [%d]\n", __func__,
198                                ecryptfs_dentry->d_name.name, rc);
199                         goto out;
200                 }
201         }
202         rc = ecryptfs_write_metadata(ecryptfs_dentry);
203         if (rc) {
204                 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
205                 goto out;
206         }
207         rc = grow_file(ecryptfs_dentry);
208         if (rc)
209                 printk(KERN_ERR "Error growing file; rc = [%d]\n", rc);
210 out:
211         return rc;
212 }
213
214 /**
215  * ecryptfs_create
216  * @dir: The inode of the directory in which to create the file.
217  * @dentry: The eCryptfs dentry
218  * @mode: The mode of the new file.
219  * @nd: nameidata
220  *
221  * Creates a new file.
222  *
223  * Returns zero on success; non-zero on error condition
224  */
225 static int
226 ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
227                 int mode, struct nameidata *nd)
228 {
229         int rc;
230
231         /* ecryptfs_do_create() calls ecryptfs_interpose() */
232         rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
233         if (unlikely(rc)) {
234                 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
235                                 "lower filesystem\n");
236                 goto out;
237         }
238         /* At this point, a file exists on "disk"; we need to make sure
239          * that this on disk file is prepared to be an ecryptfs file */
240         rc = ecryptfs_initialize_file(ecryptfs_dentry);
241 out:
242         return rc;
243 }
244
245 /**
246  * ecryptfs_lookup_and_interpose_lower - Perform a lookup
247  */
248 int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
249                                         struct dentry *lower_dentry,
250                                         struct inode *ecryptfs_dir_inode,
251                                         struct nameidata *ecryptfs_nd)
252 {
253         struct dentry *lower_dir_dentry;
254         struct vfsmount *lower_mnt;
255         struct inode *lower_inode;
256         struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
257         struct ecryptfs_crypt_stat *crypt_stat;
258         char *page_virt = NULL;
259         u64 file_size;
260         int rc = 0;
261
262         lower_dir_dentry = lower_dentry->d_parent;
263         lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
264                                    ecryptfs_dentry->d_parent));
265         lower_inode = lower_dentry->d_inode;
266         fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode);
267         BUG_ON(!atomic_read(&lower_dentry->d_count));
268         ecryptfs_set_dentry_private(ecryptfs_dentry,
269                                     kmem_cache_alloc(ecryptfs_dentry_info_cache,
270                                                      GFP_KERNEL));
271         if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) {
272                 rc = -ENOMEM;
273                 printk(KERN_ERR "%s: Out of memory whilst attempting "
274                        "to allocate ecryptfs_dentry_info struct\n",
275                         __func__);
276                 goto out_dput;
277         }
278         ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry);
279         ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt);
280         if (!lower_dentry->d_inode) {
281                 /* We want to add because we couldn't find in lower */
282                 d_add(ecryptfs_dentry, NULL);
283                 goto out;
284         }
285         rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
286                                 ecryptfs_dir_inode->i_sb,
287                                 ECRYPTFS_INTERPOSE_FLAG_D_ADD);
288         if (rc) {
289                 printk(KERN_ERR "%s: Error interposing; rc = [%d]\n",
290                        __func__, rc);
291                 goto out;
292         }
293         if (S_ISDIR(lower_inode->i_mode))
294                 goto out;
295         if (S_ISLNK(lower_inode->i_mode))
296                 goto out;
297         if (special_file(lower_inode->i_mode))
298                 goto out;
299         if (!ecryptfs_nd)
300                 goto out;
301         /* Released in this function */
302         page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER);
303         if (!page_virt) {
304                 printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n",
305                        __func__);
306                 rc = -ENOMEM;
307                 goto out;
308         }
309         if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
310                 rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
311                 if (rc) {
312                         printk(KERN_ERR "%s: Error attempting to initialize "
313                                "the persistent file for the dentry with name "
314                                "[%s]; rc = [%d]\n", __func__,
315                                ecryptfs_dentry->d_name.name, rc);
316                         goto out_free_kmem;
317                 }
318         }
319         crypt_stat = &ecryptfs_inode_to_private(
320                                         ecryptfs_dentry->d_inode)->crypt_stat;
321         /* TODO: lock for crypt_stat comparison */
322         if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
323                         ecryptfs_set_default_sizes(crypt_stat);
324         rc = ecryptfs_read_and_validate_header_region(page_virt,
325                                                       ecryptfs_dentry->d_inode);
326         if (rc) {
327                 memset(page_virt, 0, PAGE_CACHE_SIZE);
328                 rc = ecryptfs_read_and_validate_xattr_region(page_virt,
329                                                              ecryptfs_dentry);
330                 if (rc) {
331                         rc = 0;
332                         goto out_free_kmem;
333                 }
334                 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
335         }
336         mount_crypt_stat = &ecryptfs_superblock_to_private(
337                 ecryptfs_dentry->d_sb)->mount_crypt_stat;
338         if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
339                 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
340                         file_size = (crypt_stat->metadata_size
341                                      + i_size_read(lower_dentry->d_inode));
342                 else
343                         file_size = i_size_read(lower_dentry->d_inode);
344         } else {
345                 file_size = get_unaligned_be64(page_virt);
346         }
347         i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size);
348 out_free_kmem:
349         kmem_cache_free(ecryptfs_header_cache_2, page_virt);
350         goto out;
351 out_dput:
352         dput(lower_dentry);
353         d_drop(ecryptfs_dentry);
354 out:
355         return rc;
356 }
357
358 /**
359  * ecryptfs_lookup
360  * @ecryptfs_dir_inode: The eCryptfs directory inode
361  * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
362  * @ecryptfs_nd: nameidata; may be NULL
363  *
364  * Find a file on disk. If the file does not exist, then we'll add it to the
365  * dentry cache and continue on to read it from the disk.
366  */
367 static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
368                                       struct dentry *ecryptfs_dentry,
369                                       struct nameidata *ecryptfs_nd)
370 {
371         char *encrypted_and_encoded_name = NULL;
372         size_t encrypted_and_encoded_name_size;
373         struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
374         struct dentry *lower_dir_dentry, *lower_dentry;
375         int rc = 0;
376
377         ecryptfs_dentry->d_op = &ecryptfs_dops;
378         if ((ecryptfs_dentry->d_name.len == 1
379              && !strcmp(ecryptfs_dentry->d_name.name, "."))
380             || (ecryptfs_dentry->d_name.len == 2
381                 && !strcmp(ecryptfs_dentry->d_name.name, ".."))) {
382                 goto out_d_drop;
383         }
384         lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
385         mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
386         lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,
387                                       lower_dir_dentry,
388                                       ecryptfs_dentry->d_name.len);
389         mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
390         if (IS_ERR(lower_dentry)) {
391                 rc = PTR_ERR(lower_dentry);
392                 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
393                                 "[%d] on lower_dentry = [%s]\n", __func__, rc,
394                                 encrypted_and_encoded_name);
395                 goto out_d_drop;
396         }
397         if (lower_dentry->d_inode)
398                 goto lookup_and_interpose;
399         mount_crypt_stat = &ecryptfs_superblock_to_private(
400                                 ecryptfs_dentry->d_sb)->mount_crypt_stat;
401         if (!(mount_crypt_stat
402             && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
403                 goto lookup_and_interpose;
404         dput(lower_dentry);
405         rc = ecryptfs_encrypt_and_encode_filename(
406                 &encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
407                 NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name,
408                 ecryptfs_dentry->d_name.len);
409         if (rc) {
410                 printk(KERN_ERR "%s: Error attempting to encrypt and encode "
411                        "filename; rc = [%d]\n", __func__, rc);
412                 goto out_d_drop;
413         }
414         mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
415         lower_dentry = lookup_one_len(encrypted_and_encoded_name,
416                                       lower_dir_dentry,
417                                       encrypted_and_encoded_name_size - 1);
418         mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
419         if (IS_ERR(lower_dentry)) {
420                 rc = PTR_ERR(lower_dentry);
421                 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
422                                 "[%d] on lower_dentry = [%s]\n", __func__, rc,
423                                 encrypted_and_encoded_name);
424                 goto out_d_drop;
425         }
426 lookup_and_interpose:
427         rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry,
428                                                  ecryptfs_dir_inode,
429                                                  ecryptfs_nd);
430         goto out;
431 out_d_drop:
432         d_drop(ecryptfs_dentry);
433 out:
434         kfree(encrypted_and_encoded_name);
435         return ERR_PTR(rc);
436 }
437
438 static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
439                          struct dentry *new_dentry)
440 {
441         struct dentry *lower_old_dentry;
442         struct dentry *lower_new_dentry;
443         struct dentry *lower_dir_dentry;
444         u64 file_size_save;
445         int rc;
446
447         file_size_save = i_size_read(old_dentry->d_inode);
448         lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
449         lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
450         dget(lower_old_dentry);
451         dget(lower_new_dentry);
452         lower_dir_dentry = lock_parent(lower_new_dentry);
453         rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
454                       lower_new_dentry);
455         if (rc || !lower_new_dentry->d_inode)
456                 goto out_lock;
457         rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
458         if (rc)
459                 goto out_lock;
460         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
461         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
462         old_dentry->d_inode->i_nlink =
463                 ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
464         i_size_write(new_dentry->d_inode, file_size_save);
465 out_lock:
466         unlock_dir(lower_dir_dentry);
467         dput(lower_new_dentry);
468         dput(lower_old_dentry);
469         return rc;
470 }
471
472 static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
473 {
474         int rc = 0;
475         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
476         struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
477         struct dentry *lower_dir_dentry;
478
479         dget(lower_dentry);
480         lower_dir_dentry = lock_parent(lower_dentry);
481         rc = vfs_unlink(lower_dir_inode, lower_dentry);
482         if (rc) {
483                 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
484                 goto out_unlock;
485         }
486         fsstack_copy_attr_times(dir, lower_dir_inode);
487         dentry->d_inode->i_nlink =
488                 ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
489         dentry->d_inode->i_ctime = dir->i_ctime;
490         d_drop(dentry);
491 out_unlock:
492         unlock_dir(lower_dir_dentry);
493         dput(lower_dentry);
494         return rc;
495 }
496
497 static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
498                             const char *symname)
499 {
500         int rc;
501         struct dentry *lower_dentry;
502         struct dentry *lower_dir_dentry;
503         char *encoded_symname;
504         size_t encoded_symlen;
505         struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
506
507         lower_dentry = ecryptfs_dentry_to_lower(dentry);
508         dget(lower_dentry);
509         lower_dir_dentry = lock_parent(lower_dentry);
510         mount_crypt_stat = &ecryptfs_superblock_to_private(
511                 dir->i_sb)->mount_crypt_stat;
512         rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
513                                                   &encoded_symlen,
514                                                   NULL,
515                                                   mount_crypt_stat, symname,
516                                                   strlen(symname));
517         if (rc)
518                 goto out_lock;
519         rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
520                          encoded_symname);
521         kfree(encoded_symname);
522         if (rc || !lower_dentry->d_inode)
523                 goto out_lock;
524         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
525         if (rc)
526                 goto out_lock;
527         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
528         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
529 out_lock:
530         unlock_dir(lower_dir_dentry);
531         dput(lower_dentry);
532         if (!dentry->d_inode)
533                 d_drop(dentry);
534         return rc;
535 }
536
537 static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
538 {
539         int rc;
540         struct dentry *lower_dentry;
541         struct dentry *lower_dir_dentry;
542
543         lower_dentry = ecryptfs_dentry_to_lower(dentry);
544         lower_dir_dentry = lock_parent(lower_dentry);
545         rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
546         if (rc || !lower_dentry->d_inode)
547                 goto out;
548         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
549         if (rc)
550                 goto out;
551         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
552         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
553         dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
554 out:
555         unlock_dir(lower_dir_dentry);
556         if (!dentry->d_inode)
557                 d_drop(dentry);
558         return rc;
559 }
560
561 static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
562 {
563         struct dentry *lower_dentry;
564         struct dentry *lower_dir_dentry;
565         int rc;
566
567         lower_dentry = ecryptfs_dentry_to_lower(dentry);
568         dget(dentry);
569         lower_dir_dentry = lock_parent(lower_dentry);
570         dget(lower_dentry);
571         rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
572         dput(lower_dentry);
573         if (!rc)
574                 d_delete(lower_dentry);
575         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
576         dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
577         unlock_dir(lower_dir_dentry);
578         if (!rc)
579                 d_drop(dentry);
580         dput(dentry);
581         return rc;
582 }
583
584 static int
585 ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
586 {
587         int rc;
588         struct dentry *lower_dentry;
589         struct dentry *lower_dir_dentry;
590
591         lower_dentry = ecryptfs_dentry_to_lower(dentry);
592         lower_dir_dentry = lock_parent(lower_dentry);
593         rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
594         if (rc || !lower_dentry->d_inode)
595                 goto out;
596         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
597         if (rc)
598                 goto out;
599         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
600         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
601 out:
602         unlock_dir(lower_dir_dentry);
603         if (!dentry->d_inode)
604                 d_drop(dentry);
605         return rc;
606 }
607
608 static int
609 ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
610                 struct inode *new_dir, struct dentry *new_dentry)
611 {
612         int rc;
613         struct dentry *lower_old_dentry;
614         struct dentry *lower_new_dentry;
615         struct dentry *lower_old_dir_dentry;
616         struct dentry *lower_new_dir_dentry;
617         struct dentry *trap = NULL;
618
619         lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
620         lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
621         dget(lower_old_dentry);
622         dget(lower_new_dentry);
623         lower_old_dir_dentry = dget_parent(lower_old_dentry);
624         lower_new_dir_dentry = dget_parent(lower_new_dentry);
625         trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
626         /* source should not be ancestor of target */
627         if (trap == lower_old_dentry) {
628                 rc = -EINVAL;
629                 goto out_lock;
630         }
631         /* target should not be ancestor of source */
632         if (trap == lower_new_dentry) {
633                 rc = -ENOTEMPTY;
634                 goto out_lock;
635         }
636         rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
637                         lower_new_dir_dentry->d_inode, lower_new_dentry);
638         if (rc)
639                 goto out_lock;
640         fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
641         if (new_dir != old_dir)
642                 fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
643 out_lock:
644         unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
645         dput(lower_new_dentry->d_parent);
646         dput(lower_old_dentry->d_parent);
647         dput(lower_new_dentry);
648         dput(lower_old_dentry);
649         return rc;
650 }
651
652 static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf,
653                                    size_t *bufsiz)
654 {
655         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
656         char *lower_buf;
657         size_t lower_bufsiz = PATH_MAX;
658         mm_segment_t old_fs;
659         int rc;
660
661         lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
662         if (!lower_buf) {
663                 rc = -ENOMEM;
664                 goto out;
665         }
666         old_fs = get_fs();
667         set_fs(get_ds());
668         rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
669                                                    (char __user *)lower_buf,
670                                                    lower_bufsiz);
671         set_fs(old_fs);
672         if (rc < 0)
673                 goto out;
674         lower_bufsiz = rc;
675         rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry,
676                                                   lower_buf, lower_bufsiz);
677 out:
678         kfree(lower_buf);
679         return rc;
680 }
681
682 static int
683 ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
684 {
685         char *kbuf;
686         size_t kbufsiz, copied;
687         int rc;
688
689         rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz);
690         if (rc)
691                 goto out;
692         copied = min_t(size_t, bufsiz, kbufsiz);
693         rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied;
694         kfree(kbuf);
695         fsstack_copy_attr_atime(dentry->d_inode,
696                                 ecryptfs_dentry_to_lower(dentry)->d_inode);
697 out:
698         return rc;
699 }
700
701 static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
702 {
703         char *buf;
704         int len = PAGE_SIZE, rc;
705         mm_segment_t old_fs;
706
707         /* Released in ecryptfs_put_link(); only release here on error */
708         buf = kmalloc(len, GFP_KERNEL);
709         if (!buf) {
710                 buf = ERR_PTR(-ENOMEM);
711                 goto out;
712         }
713         old_fs = get_fs();
714         set_fs(get_ds());
715         rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
716         set_fs(old_fs);
717         if (rc < 0) {
718                 kfree(buf);
719                 buf = ERR_PTR(rc);
720         } else
721                 buf[rc] = '\0';
722 out:
723         nd_set_link(nd, buf);
724         return NULL;
725 }
726
727 static void
728 ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
729 {
730         char *buf = nd_get_link(nd);
731         if (!IS_ERR(buf)) {
732                 /* Free the char* */
733                 kfree(buf);
734         }
735 }
736
737 /**
738  * upper_size_to_lower_size
739  * @crypt_stat: Crypt_stat associated with file
740  * @upper_size: Size of the upper file
741  *
742  * Calculate the required size of the lower file based on the
743  * specified size of the upper file. This calculation is based on the
744  * number of headers in the underlying file and the extent size.
745  *
746  * Returns Calculated size of the lower file.
747  */
748 static loff_t
749 upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
750                          loff_t upper_size)
751 {
752         loff_t lower_size;
753
754         lower_size = ecryptfs_lower_header_size(crypt_stat);
755         if (upper_size != 0) {
756                 loff_t num_extents;
757
758                 num_extents = upper_size >> crypt_stat->extent_shift;
759                 if (upper_size & ~crypt_stat->extent_mask)
760                         num_extents++;
761                 lower_size += (num_extents * crypt_stat->extent_size);
762         }
763         return lower_size;
764 }
765
766 /**
767  * truncate_upper
768  * @dentry: The ecryptfs layer dentry
769  * @ia: Address of the ecryptfs inode's attributes
770  * @lower_ia: Address of the lower inode's attributes
771  *
772  * Function to handle truncations modifying the size of the file. Note
773  * that the file sizes are interpolated. When expanding, we are simply
774  * writing strings of 0's out. When truncating, we truncate the upper
775  * inode and update the lower_ia according to the page index
776  * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
777  * the caller must use lower_ia in a call to notify_change() to perform
778  * the truncation of the lower inode.
779  *
780  * Returns zero on success; non-zero otherwise
781  */
782 static int truncate_upper(struct dentry *dentry, struct iattr *ia,
783                           struct iattr *lower_ia)
784 {
785         int rc = 0;
786         struct inode *inode = dentry->d_inode;
787         struct dentry *lower_dentry;
788         struct file fake_ecryptfs_file;
789         struct ecryptfs_crypt_stat *crypt_stat;
790         loff_t i_size = i_size_read(inode);
791         loff_t lower_size_before_truncate;
792         loff_t lower_size_after_truncate;
793
794         if (unlikely((ia->ia_size == i_size))) {
795                 lower_ia->ia_valid &= ~ATTR_SIZE;
796                 goto out;
797         }
798         crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
799         /* Set up a fake ecryptfs file, this is used to interface with
800          * the file in the underlying filesystem so that the
801          * truncation has an effect there as well. */
802         memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file));
803         fake_ecryptfs_file.f_path.dentry = dentry;
804         /* Released at out_free: label */
805         ecryptfs_set_file_private(&fake_ecryptfs_file,
806                                   kmem_cache_alloc(ecryptfs_file_info_cache,
807                                                    GFP_KERNEL));
808         if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) {
809                 rc = -ENOMEM;
810                 goto out;
811         }
812         lower_dentry = ecryptfs_dentry_to_lower(dentry);
813         ecryptfs_set_file_lower(
814                 &fake_ecryptfs_file,
815                 ecryptfs_inode_to_private(dentry->d_inode)->lower_file);
816         /* Switch on growing or shrinking file */
817         if (ia->ia_size > i_size) {
818                 char zero[] = { 0x00 };
819
820                 lower_ia->ia_valid &= ~ATTR_SIZE;
821                 /* Write a single 0 at the last position of the file;
822                  * this triggers code that will fill in 0's throughout
823                  * the intermediate portion of the previous end of the
824                  * file and the new and of the file */
825                 rc = ecryptfs_write(&fake_ecryptfs_file, zero,
826                                     (ia->ia_size - 1), 1);
827         } else { /* ia->ia_size < i_size_read(inode) */
828                 /* We're chopping off all the pages down to the page
829                  * in which ia->ia_size is located. Fill in the end of
830                  * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to
831                  * PAGE_CACHE_SIZE with zeros. */
832                 size_t num_zeros = (PAGE_CACHE_SIZE
833                                     - (ia->ia_size & ~PAGE_CACHE_MASK));
834
835                 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
836                         rc = vmtruncate(inode, ia->ia_size);
837                         if (rc)
838                                 goto out_free;
839                         lower_ia->ia_size = ia->ia_size;
840                         lower_ia->ia_valid |= ATTR_SIZE;
841                         goto out_free;
842                 }
843                 if (num_zeros) {
844                         char *zeros_virt;
845
846                         zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
847                         if (!zeros_virt) {
848                                 rc = -ENOMEM;
849                                 goto out_free;
850                         }
851                         rc = ecryptfs_write(&fake_ecryptfs_file, zeros_virt,
852                                             ia->ia_size, num_zeros);
853                         kfree(zeros_virt);
854                         if (rc) {
855                                 printk(KERN_ERR "Error attempting to zero out "
856                                        "the remainder of the end page on "
857                                        "reducing truncate; rc = [%d]\n", rc);
858                                 goto out_free;
859                         }
860                 }
861                 vmtruncate(inode, ia->ia_size);
862                 rc = ecryptfs_write_inode_size_to_metadata(inode);
863                 if (rc) {
864                         printk(KERN_ERR "Problem with "
865                                "ecryptfs_write_inode_size_to_metadata; "
866                                "rc = [%d]\n", rc);
867                         goto out_free;
868                 }
869                 /* We are reducing the size of the ecryptfs file, and need to
870                  * know if we need to reduce the size of the lower file. */
871                 lower_size_before_truncate =
872                     upper_size_to_lower_size(crypt_stat, i_size);
873                 lower_size_after_truncate =
874                     upper_size_to_lower_size(crypt_stat, ia->ia_size);
875                 if (lower_size_after_truncate < lower_size_before_truncate) {
876                         lower_ia->ia_size = lower_size_after_truncate;
877                         lower_ia->ia_valid |= ATTR_SIZE;
878                 } else
879                         lower_ia->ia_valid &= ~ATTR_SIZE;
880         }
881 out_free:
882         if (ecryptfs_file_to_private(&fake_ecryptfs_file))
883                 kmem_cache_free(ecryptfs_file_info_cache,
884                                 ecryptfs_file_to_private(&fake_ecryptfs_file));
885 out:
886         return rc;
887 }
888
889 /**
890  * ecryptfs_truncate
891  * @dentry: The ecryptfs layer dentry
892  * @new_length: The length to expand the file to
893  *
894  * Simple function that handles the truncation of an eCryptfs inode and
895  * its corresponding lower inode.
896  *
897  * Returns zero on success; non-zero otherwise
898  */
899 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
900 {
901         struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
902         struct iattr lower_ia = { .ia_valid = 0 };
903         int rc;
904
905         rc = truncate_upper(dentry, &ia, &lower_ia);
906         if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
907                 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
908
909                 mutex_lock(&lower_dentry->d_inode->i_mutex);
910                 rc = notify_change(lower_dentry, &lower_ia);
911                 mutex_unlock(&lower_dentry->d_inode->i_mutex);
912         }
913         return rc;
914 }
915
916 static int
917 ecryptfs_permission(struct inode *inode, int mask)
918 {
919         return inode_permission(ecryptfs_inode_to_lower(inode), mask);
920 }
921
922 /**
923  * ecryptfs_setattr
924  * @dentry: dentry handle to the inode to modify
925  * @ia: Structure with flags of what to change and values
926  *
927  * Updates the metadata of an inode. If the update is to the size
928  * i.e. truncation, then ecryptfs_truncate will handle the size modification
929  * of both the ecryptfs inode and the lower inode.
930  *
931  * All other metadata changes will be passed right to the lower filesystem,
932  * and we will just update our inode to look like the lower.
933  */
934 static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
935 {
936         int rc = 0;
937         struct dentry *lower_dentry;
938         struct iattr lower_ia;
939         struct inode *inode;
940         struct inode *lower_inode;
941         struct ecryptfs_crypt_stat *crypt_stat;
942
943         crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
944         if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
945                 ecryptfs_init_crypt_stat(crypt_stat);
946         inode = dentry->d_inode;
947         lower_inode = ecryptfs_inode_to_lower(inode);
948         lower_dentry = ecryptfs_dentry_to_lower(dentry);
949         mutex_lock(&crypt_stat->cs_mutex);
950         if (S_ISDIR(dentry->d_inode->i_mode))
951                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
952         else if (S_ISREG(dentry->d_inode->i_mode)
953                  && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
954                      || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
955                 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
956
957                 mount_crypt_stat = &ecryptfs_superblock_to_private(
958                         dentry->d_sb)->mount_crypt_stat;
959                 rc = ecryptfs_read_metadata(dentry);
960                 if (rc) {
961                         if (!(mount_crypt_stat->flags
962                               & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
963                                 rc = -EIO;
964                                 printk(KERN_WARNING "Either the lower file "
965                                        "is not in a valid eCryptfs format, "
966                                        "or the key could not be retrieved. "
967                                        "Plaintext passthrough mode is not "
968                                        "enabled; returning -EIO\n");
969                                 mutex_unlock(&crypt_stat->cs_mutex);
970                                 goto out;
971                         }
972                         rc = 0;
973                         crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
974                 }
975         }
976         mutex_unlock(&crypt_stat->cs_mutex);
977         memcpy(&lower_ia, ia, sizeof(lower_ia));
978         if (ia->ia_valid & ATTR_FILE)
979                 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
980         if (ia->ia_valid & ATTR_SIZE) {
981                 rc = truncate_upper(dentry, ia, &lower_ia);
982                 if (rc < 0)
983                         goto out;
984         }
985
986         /*
987          * mode change is for clearing setuid/setgid bits. Allow lower fs
988          * to interpret this in its own way.
989          */
990         if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
991                 lower_ia.ia_valid &= ~ATTR_MODE;
992
993         mutex_lock(&lower_dentry->d_inode->i_mutex);
994         rc = notify_change(lower_dentry, &lower_ia);
995         mutex_unlock(&lower_dentry->d_inode->i_mutex);
996 out:
997         fsstack_copy_attr_all(inode, lower_inode);
998         return rc;
999 }
1000
1001 int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
1002                           struct kstat *stat)
1003 {
1004         struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
1005         int rc = 0;
1006
1007         mount_crypt_stat = &ecryptfs_superblock_to_private(
1008                                                 dentry->d_sb)->mount_crypt_stat;
1009         generic_fillattr(dentry->d_inode, stat);
1010         if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
1011                 char *target;
1012                 size_t targetsiz;
1013
1014                 rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz);
1015                 if (!rc) {
1016                         kfree(target);
1017                         stat->size = targetsiz;
1018                 }
1019         }
1020         return rc;
1021 }
1022
1023 int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1024                      struct kstat *stat)
1025 {
1026         struct kstat lower_stat;
1027         int rc;
1028
1029         rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry),
1030                          ecryptfs_dentry_to_lower(dentry), &lower_stat);
1031         if (!rc) {
1032                 generic_fillattr(dentry->d_inode, stat);
1033                 stat->blocks = lower_stat.blocks;
1034         }
1035         return rc;
1036 }
1037
1038 int
1039 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
1040                   size_t size, int flags)
1041 {
1042         int rc = 0;
1043         struct dentry *lower_dentry;
1044
1045         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1046         if (!lower_dentry->d_inode->i_op->setxattr) {
1047                 rc = -EOPNOTSUPP;
1048                 goto out;
1049         }
1050         mutex_lock(&lower_dentry->d_inode->i_mutex);
1051         rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value,
1052                                                    size, flags);
1053         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1054 out:
1055         return rc;
1056 }
1057
1058 ssize_t
1059 ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
1060                         void *value, size_t size)
1061 {
1062         int rc = 0;
1063
1064         if (!lower_dentry->d_inode->i_op->getxattr) {
1065                 rc = -EOPNOTSUPP;
1066                 goto out;
1067         }
1068         mutex_lock(&lower_dentry->d_inode->i_mutex);
1069         rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
1070                                                    size);
1071         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1072 out:
1073         return rc;
1074 }
1075
1076 static ssize_t
1077 ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
1078                   size_t size)
1079 {
1080         return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
1081                                        value, size);
1082 }
1083
1084 static ssize_t
1085 ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1086 {
1087         int rc = 0;
1088         struct dentry *lower_dentry;
1089
1090         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1091         if (!lower_dentry->d_inode->i_op->listxattr) {
1092                 rc = -EOPNOTSUPP;
1093                 goto out;
1094         }
1095         mutex_lock(&lower_dentry->d_inode->i_mutex);
1096         rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
1097         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1098 out:
1099         return rc;
1100 }
1101
1102 static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
1103 {
1104         int rc = 0;
1105         struct dentry *lower_dentry;
1106
1107         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1108         if (!lower_dentry->d_inode->i_op->removexattr) {
1109                 rc = -EOPNOTSUPP;
1110                 goto out;
1111         }
1112         mutex_lock(&lower_dentry->d_inode->i_mutex);
1113         rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
1114         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1115 out:
1116         return rc;
1117 }
1118
1119 int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
1120 {
1121         if ((ecryptfs_inode_to_lower(inode)
1122              == (struct inode *)candidate_lower_inode))
1123                 return 1;
1124         else
1125                 return 0;
1126 }
1127
1128 int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
1129 {
1130         ecryptfs_init_inode(inode, (struct inode *)lower_inode);
1131         return 0;
1132 }
1133
1134 const struct inode_operations ecryptfs_symlink_iops = {
1135         .readlink = ecryptfs_readlink,
1136         .follow_link = ecryptfs_follow_link,
1137         .put_link = ecryptfs_put_link,
1138         .permission = ecryptfs_permission,
1139         .setattr = ecryptfs_setattr,
1140         .getattr = ecryptfs_getattr_link,
1141         .setxattr = ecryptfs_setxattr,
1142         .getxattr = ecryptfs_getxattr,
1143         .listxattr = ecryptfs_listxattr,
1144         .removexattr = ecryptfs_removexattr
1145 };
1146
1147 const struct inode_operations ecryptfs_dir_iops = {
1148         .create = ecryptfs_create,
1149         .lookup = ecryptfs_lookup,
1150         .link = ecryptfs_link,
1151         .unlink = ecryptfs_unlink,
1152         .symlink = ecryptfs_symlink,
1153         .mkdir = ecryptfs_mkdir,
1154         .rmdir = ecryptfs_rmdir,
1155         .mknod = ecryptfs_mknod,
1156         .rename = ecryptfs_rename,
1157         .permission = ecryptfs_permission,
1158         .setattr = ecryptfs_setattr,
1159         .setxattr = ecryptfs_setxattr,
1160         .getxattr = ecryptfs_getxattr,
1161         .listxattr = ecryptfs_listxattr,
1162         .removexattr = ecryptfs_removexattr
1163 };
1164
1165 const struct inode_operations ecryptfs_main_iops = {
1166         .permission = ecryptfs_permission,
1167         .setattr = ecryptfs_setattr,
1168         .getattr = ecryptfs_getattr,
1169         .setxattr = ecryptfs_setxattr,
1170         .getxattr = ecryptfs_getxattr,
1171         .listxattr = ecryptfs_listxattr,
1172         .removexattr = ecryptfs_removexattr
1173 };