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