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