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