fs/ecryptfs/inode.c

   1 /**
   2  * eCryptfs: Linux filesystem encryption layer
   3  *
   4  * Copyright (C) 1997-2004 Erez Zadok
   5  * Copyright (C) 2001-2004 Stony Brook University
   6  * Copyright (C) 2004-2007 International Business Machines Corp.
   7  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
   8  *              Michael C. Thompsion <mcthomps@us.ibm.com>
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License as
  12  * published by the Free Software Foundation; either version 2 of the
  13  * License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  23  * 02111-1307, USA.
  24  */
  25
  26 #include <linux/file.h>
  27 #include <linux/vmalloc.h>
  28 #include <linux/pagemap.h>
  29 #include <linux/dcache.h>
  30 #include <linux/namei.h>
  31 #include <linux/mount.h>
  32 #include <linux/crypto.h>
  33 #include <linux/fs_stack.h>
  34 #include <linux/slab.h>
  35 #include <asm/unaligned.h>
  36 #include "ecryptfs_kernel.h"
  37
  38 static struct dentry *lock_parent(struct dentry *dentry)
  39 {
  40         struct dentry *dir;
  41
  42         dir = dget_parent(dentry);
  43         mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT);
  44         return dir;
  45 }
  46
  47 static void unlock_dir(struct dentry *dir)
  48 {
  49         mutex_unlock(&dir->d_inode->i_mutex);
  50         dput(dir);
  51 }
  52
  53 /**
  54  * ecryptfs_create_underlying_file
  55  * @lower_dir_inode: inode of the parent in the lower fs of the new file
  56  * @dentry: New file's dentry
  57  * @mode: The mode of the new file
  58  * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
  59  *
  60  * Creates the file in the lower file system.
  61  *
  62  * Returns zero on success; non-zero on error condition
  63  */
  64 static int
  65 ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
  66                                 struct dentry *dentry, int mode,
  67                                 struct nameidata *nd)
  68 {
  69         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
  70         struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
  71         struct dentry *dentry_save;
  72         struct vfsmount *vfsmount_save;
  73         int rc;
  74
  75         dentry_save = nd->path.dentry;
  76         vfsmount_save = nd->path.mnt;
  77         nd->path.dentry = lower_dentry;
  78         nd->path.mnt = lower_mnt;
  79         rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
  80         nd->path.dentry = dentry_save;
  81         nd->path.mnt = vfsmount_save;
  82         return rc;
  83 }
  84
  85 /**
  86  * ecryptfs_do_create
  87  * @directory_inode: inode of the new file's dentry's parent in ecryptfs
  88  * @ecryptfs_dentry: New file's dentry in ecryptfs
  89  * @mode: The mode of the new file
  90  * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
  91  *
  92  * Creates the underlying file and the eCryptfs inode which will link to
  93  * it. It will also update the eCryptfs directory inode to mimic the
  94  * stat of the lower directory inode.
  95  *
  96  * Returns zero on success; non-zero on error condition
  97  */
  98 static int
  99 ecryptfs_do_create(struct inode *directory_inode,
 100                    struct dentry *ecryptfs_dentry, int mode,
 101                    struct nameidata *nd)
 102 {
 103         int rc;
 104         struct dentry *lower_dentry;
 105         struct dentry *lower_dir_dentry;
 106
 107         lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
 108         lower_dir_dentry = lock_parent(lower_dentry);
 109         if (IS_ERR(lower_dir_dentry)) {
 110                 ecryptfs_printk(KERN_ERR, "Error locking directory of "
 111                                 "dentry\n");
 112                 rc = PTR_ERR(lower_dir_dentry);
 113                 goto out;
 114         }
 115         rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
 116                                              ecryptfs_dentry, mode, nd);
 117         if (rc) {
 118                 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
 119                        "rc = [%d]\n", __func__, rc);
 120                 goto out_lock;
 121         }
 122         rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
 123                                 directory_inode->i_sb, 0);
 124         if (rc) {
 125                 ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
 126                 goto out_lock;
 127         }
 128         fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
 129         fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
 130 out_lock:
 131         unlock_dir(lower_dir_dentry);
 132 out:
 133         return rc;
 134 }
 135
 136 /**
 137  * grow_file
 138  * @ecryptfs_dentry: the eCryptfs dentry
 139  *
 140  * This is the code which will grow the file to its correct size.
 141  */
 142 static int grow_file(struct dentry *ecryptfs_dentry)
 143 {
 144         struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
 145         char zero_virt[] = { 0x00 };
 146         int rc = 0;
 147
 148         rc = ecryptfs_write(ecryptfs_inode, zero_virt, 0, 1);
 149         i_size_write(ecryptfs_inode, 0);
 150         rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
 151         ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |=
 152                 ECRYPTFS_NEW_FILE;
 153         return rc;
 154 }
 155
 156 /**
 157  * ecryptfs_initialize_file
 158  *
 159  * Cause the file to be changed from a basic empty file to an ecryptfs
 160  * file with a header and first data page.
 161  *
 162  * Returns zero on success
 163  */
 164 static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
 165 {
 166         struct ecryptfs_crypt_stat *crypt_stat =
 167                 &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
 168         int rc = 0;
 169
 170         if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
 171                 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
 172                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
 173                 goto out;
 174         }
 175         crypt_stat->flags |= ECRYPTFS_NEW_FILE;
 176         ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
 177         rc = ecryptfs_new_file_context(ecryptfs_dentry);
 178         if (rc) {
 179                 ecryptfs_printk(KERN_ERR, "Error creating new file "
 180                                 "context; rc = [%d]\n", rc);
 181                 goto out;
 182         }
 183         if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
 184                 rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
 185                 if (rc) {
 186                         printk(KERN_ERR "%s: Error attempting to initialize "
 187                                "the persistent file for the dentry with name "
 188                                "[%s]; rc = [%d]\n", __func__,
 189                                ecryptfs_dentry->d_name.name, rc);
 190                         goto out;
 191                 }
 192         }
 193         rc = ecryptfs_write_metadata(ecryptfs_dentry);
 194         if (rc) {
 195                 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
 196                 goto out;
 197         }
 198         rc = grow_file(ecryptfs_dentry);
 199         if (rc)
 200                 printk(KERN_ERR "Error growing file; rc = [%d]\n", rc);
 201 out:
 202         return rc;
 203 }
 204
 205 /**
 206  * ecryptfs_create
 207  * @dir: The inode of the directory in which to create the file.
 208  * @dentry: The eCryptfs dentry
 209  * @mode: The mode of the new file.
 210  * @nd: nameidata
 211  *
 212  * Creates a new file.
 213  *
 214  * Returns zero on success; non-zero on error condition
 215  */
 216 static int
 217 ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
 218                 int mode, struct nameidata *nd)
 219 {
 220         int rc;
 221
 222         /* ecryptfs_do_create() calls ecryptfs_interpose() */
 223         rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
 224         if (unlikely(rc)) {
 225                 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
 226                                 "lower filesystem\n");
 227                 goto out;
 228         }
 229         /* At this point, a file exists on "disk"; we need to make sure
 230          * that this on disk file is prepared to be an ecryptfs file */
 231         rc = ecryptfs_initialize_file(ecryptfs_dentry);
 232 out:
 233         return rc;
 234 }
 235
 236 /**
 237  * ecryptfs_lookup_and_interpose_lower - Perform a lookup
 238  */
 239 int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
 240                                         struct dentry *lower_dentry,
 241                                         struct inode *ecryptfs_dir_inode,
 242                                         struct nameidata *ecryptfs_nd)
 243 {
 244         struct dentry *lower_dir_dentry;
 245         struct vfsmount *lower_mnt;
 246         struct inode *lower_inode;
 247         struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 248         struct ecryptfs_crypt_stat *crypt_stat;
 249         char *page_virt = NULL;
 250         u64 file_size;
 251         int rc = 0;
 252
 253         lower_dir_dentry = lower_dentry->d_parent;
 254         lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
 255                                    ecryptfs_dentry->d_parent));
 256         lower_inode = lower_dentry->d_inode;
 257         fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode);
 258         BUG_ON(!atomic_read(&lower_dentry->d_count));
 259         ecryptfs_set_dentry_private(ecryptfs_dentry,
 260                                     kmem_cache_alloc(ecryptfs_dentry_info_cache,
 261                                                      GFP_KERNEL));
 262         if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) {
 263                 rc = -ENOMEM;
 264                 printk(KERN_ERR "%s: Out of memory whilst attempting "
 265                        "to allocate ecryptfs_dentry_info struct\n",
 266                         __func__);
 267                 goto out_put;
 268         }
 269         ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry);
 270         ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt);
 271         if (!lower_dentry->d_inode) {
 272                 /* We want to add because we couldn't find in lower */
 273                 d_add(ecryptfs_dentry, NULL);
 274                 goto out;
 275         }
 276         rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
 277                                 ecryptfs_dir_inode->i_sb,
 278                                 ECRYPTFS_INTERPOSE_FLAG_D_ADD);
 279         if (rc) {
 280                 printk(KERN_ERR "%s: Error interposing; rc = [%d]\n",
 281                        __func__, rc);
 282                 goto out;
 283         }
 284         if (S_ISDIR(lower_inode->i_mode))
 285                 goto out;
 286         if (S_ISLNK(lower_inode->i_mode))
 287                 goto out;
 288         if (special_file(lower_inode->i_mode))
 289                 goto out;
 290         if (!ecryptfs_nd)
 291                 goto out;
 292         /* Released in this function */
 293         page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER);
 294         if (!page_virt) {
 295                 printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n",
 296                        __func__);
 297                 rc = -ENOMEM;
 298                 goto out;
 299         }
 300         if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
 301                 rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
 302                 if (rc) {
 303                         printk(KERN_ERR "%s: Error attempting to initialize "
 304                                "the persistent file for the dentry with name "
 305                                "[%s]; rc = [%d]\n", __func__,
 306                                ecryptfs_dentry->d_name.name, rc);
 307                         goto out_free_kmem;
 308                 }
 309         }
 310         crypt_stat = &ecryptfs_inode_to_private(
 311                                         ecryptfs_dentry->d_inode)->crypt_stat;
 312         /* TODO: lock for crypt_stat comparison */
 313         if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
 314                         ecryptfs_set_default_sizes(crypt_stat);
 315         rc = ecryptfs_read_and_validate_header_region(page_virt,
 316                                                       ecryptfs_dentry->d_inode);
 317         if (rc) {
 318                 memset(page_virt, 0, PAGE_CACHE_SIZE);
 319                 rc = ecryptfs_read_and_validate_xattr_region(page_virt,
 320                                                              ecryptfs_dentry);
 321                 if (rc) {
 322                         rc = 0;
 323                         goto out_free_kmem;
 324                 }
 325                 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
 326         }
 327         mount_crypt_stat = &ecryptfs_superblock_to_private(
 328                 ecryptfs_dentry->d_sb)->mount_crypt_stat;
 329         if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
 330                 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
 331                         file_size = (crypt_stat->metadata_size
 332                                      + i_size_read(lower_dentry->d_inode));
 333                 else
 334                         file_size = i_size_read(lower_dentry->d_inode);
 335         } else {
 336                 file_size = get_unaligned_be64(page_virt);
 337         }
 338         i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size);
 339 out_free_kmem:
 340         kmem_cache_free(ecryptfs_header_cache_2, page_virt);
 341         goto out;
 342 out_put:
 343         dput(lower_dentry);
 344         mntput(lower_mnt);
 345         d_drop(ecryptfs_dentry);
 346 out:
 347         return rc;
 348 }
 349
 350 /**
 351  * ecryptfs_new_lower_dentry
 352  * @ename: The name of the new dentry.
 353  * @lower_dir_dentry: Parent directory of the new dentry.
 354  * @nd: nameidata from last lookup.
 355  *
 356  * Create a new dentry or get it from lower parent dir.
 357  */
 358 static struct dentry *
 359 ecryptfs_new_lower_dentry(struct qstr *name, struct dentry *lower_dir_dentry,
 360                           struct nameidata *nd)
 361 {
 362         struct dentry *new_dentry;
 363         struct dentry *tmp;
 364         struct inode *lower_dir_inode;
 365
 366         lower_dir_inode = lower_dir_dentry->d_inode;
 367
 368         tmp = d_alloc(lower_dir_dentry, name);
 369         if (!tmp)
 370                 return ERR_PTR(-ENOMEM);
 371
 372         mutex_lock(&lower_dir_inode->i_mutex);
 373         new_dentry = lower_dir_inode->i_op->lookup(lower_dir_inode, tmp, nd);
 374         mutex_unlock(&lower_dir_inode->i_mutex);
 375
 376         if (!new_dentry)
 377                 new_dentry = tmp;
 378         else
 379                 dput(tmp);
 380
 381         return new_dentry;
 382 }
 383
 384
 385 /**
 386  * ecryptfs_lookup_one_lower
 387  * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
 388  * @lower_dir_dentry: lower parent directory
 389  *
 390  * Get the lower dentry from vfs. If lower dentry does not exist yet,
 391  * create it.
 392  */
 393 static struct dentry *
 394 ecryptfs_lookup_one_lower(struct dentry *ecryptfs_dentry,
 395                           struct dentry *lower_dir_dentry)
 396 {
 397         struct nameidata nd;
 398         struct vfsmount *lower_mnt;
 399         struct qstr *name;
 400         int err;
 401
 402         name = &ecryptfs_dentry->d_name;
 403         lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
 404                                     ecryptfs_dentry->d_parent));
 405         err = vfs_path_lookup(lower_dir_dentry, lower_mnt, name->name , 0, &nd);
 406         mntput(lower_mnt);
 407
 408         if (!err) {
 409                 /* we dont need the mount */
 410                 mntput(nd.path.mnt);
 411                 return nd.path.dentry;
 412         }
 413         if (err != -ENOENT)
 414                 return ERR_PTR(err);
 415
 416         /* create a new lower dentry */
 417         return ecryptfs_new_lower_dentry(name, lower_dir_dentry, &nd);
 418 }
 419
 420 /**
 421  * ecryptfs_lookup
 422  * @ecryptfs_dir_inode: The eCryptfs directory inode
 423  * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
 424  * @ecryptfs_nd: nameidata; may be NULL
 425  *
 426  * Find a file on disk. If the file does not exist, then we'll add it to the
 427  * dentry cache and continue on to read it from the disk.
 428  */
 429 static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
 430                                       struct dentry *ecryptfs_dentry,
 431                                       struct nameidata *ecryptfs_nd)
 432 {
 433         char *encrypted_and_encoded_name = NULL;
 434         size_t encrypted_and_encoded_name_size;
 435         struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
 436         struct dentry *lower_dir_dentry, *lower_dentry;
 437         int rc = 0;
 438
 439         ecryptfs_dentry->d_op = &ecryptfs_dops;
 440         if ((ecryptfs_dentry->d_name.len == 1
 441              && !strcmp(ecryptfs_dentry->d_name.name, "."))
 442             || (ecryptfs_dentry->d_name.len == 2
 443                 && !strcmp(ecryptfs_dentry->d_name.name, ".."))) {
 444                 goto out_d_drop;
 445         }
 446         lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
 447
 448         lower_dentry = ecryptfs_lookup_one_lower(ecryptfs_dentry,
 449                                                  lower_dir_dentry);
 450         if (IS_ERR(lower_dentry)) {
 451                 rc = PTR_ERR(lower_dentry);
 452                 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_lower() returned "
 453                                 "[%d] on lower_dentry = [%s]\n", __func__, rc,
 454                                 encrypted_and_encoded_name);
 455                 goto out_d_drop;
 456         }
 457         if (lower_dentry->d_inode)
 458                 goto lookup_and_interpose;
 459         mount_crypt_stat = &ecryptfs_superblock_to_private(
 460                                 ecryptfs_dentry->d_sb)->mount_crypt_stat;
 461         if (!(mount_crypt_stat
 462             && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
 463                 goto lookup_and_interpose;
 464         dput(lower_dentry);
 465         rc = ecryptfs_encrypt_and_encode_filename(
 466                 &encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
 467                 NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name,
 468                 ecryptfs_dentry->d_name.len);
 469         if (rc) {
 470                 printk(KERN_ERR "%s: Error attempting to encrypt and encode "
 471                        "filename; rc = [%d]\n", __func__, rc);
 472                 goto out_d_drop;
 473         }
 474         lower_dentry = ecryptfs_lookup_one_lower(ecryptfs_dentry,
 475                                                  lower_dir_dentry);
 476         if (IS_ERR(lower_dentry)) {
 477                 rc = PTR_ERR(lower_dentry);
 478                 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_lower() returned "
 479                                 "[%d] on lower_dentry = [%s]\n", __func__, rc,
 480                                 encrypted_and_encoded_name);
 481                 goto out_d_drop;
 482         }
 483 lookup_and_interpose:
 484         rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry,
 485                                                  ecryptfs_dir_inode,
 486                                                  ecryptfs_nd);
 487         goto out;
 488 out_d_drop:
 489         d_drop(ecryptfs_dentry);
 490 out:
 491         kfree(encrypted_and_encoded_name);
 492         return ERR_PTR(rc);
 493 }
 494
 495 static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
 496                          struct dentry *new_dentry)
 497 {
 498         struct dentry *lower_old_dentry;
 499         struct dentry *lower_new_dentry;
 500         struct dentry *lower_dir_dentry;
 501         u64 file_size_save;
 502         int rc;
 503
 504         file_size_save = i_size_read(old_dentry->d_inode);
 505         lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
 506         lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 507         dget(lower_old_dentry);
 508         dget(lower_new_dentry);
 509         lower_dir_dentry = lock_parent(lower_new_dentry);
 510         rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
 511                       lower_new_dentry);
 512         if (rc || !lower_new_dentry->d_inode)
 513                 goto out_lock;
 514         rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
 515         if (rc)
 516                 goto out_lock;
 517         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 518         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 519         old_dentry->d_inode->i_nlink =
 520                 ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
 521         i_size_write(new_dentry->d_inode, file_size_save);
 522 out_lock:
 523         unlock_dir(lower_dir_dentry);
 524         dput(lower_new_dentry);
 525         dput(lower_old_dentry);
 526         return rc;
 527 }
 528
 529 static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
 530 {
 531         int rc = 0;
 532         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 533         struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
 534         struct dentry *lower_dir_dentry;
 535
 536         dget(lower_dentry);
 537         lower_dir_dentry = lock_parent(lower_dentry);
 538         rc = vfs_unlink(lower_dir_inode, lower_dentry);
 539         if (rc) {
 540                 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
 541                 goto out_unlock;
 542         }
 543         fsstack_copy_attr_times(dir, lower_dir_inode);
 544         dentry->d_inode->i_nlink =
 545                 ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
 546         dentry->d_inode->i_ctime = dir->i_ctime;
 547         d_drop(dentry);
 548 out_unlock:
 549         unlock_dir(lower_dir_dentry);
 550         dput(lower_dentry);
 551         return rc;
 552 }
 553
 554 static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
 555                             const char *symname)
 556 {
 557         int rc;
 558         struct dentry *lower_dentry;
 559         struct dentry *lower_dir_dentry;
 560         char *encoded_symname;
 561         size_t encoded_symlen;
 562         struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
 563
 564         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 565         dget(lower_dentry);
 566         lower_dir_dentry = lock_parent(lower_dentry);
 567         mount_crypt_stat = &ecryptfs_superblock_to_private(
 568                 dir->i_sb)->mount_crypt_stat;
 569         rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
 570                                                   &encoded_symlen,
 571                                                   NULL,
 572                                                   mount_crypt_stat, symname,
 573                                                   strlen(symname));
 574         if (rc)
 575                 goto out_lock;
 576         rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
 577                          encoded_symname);
 578         kfree(encoded_symname);
 579         if (rc || !lower_dentry->d_inode)
 580                 goto out_lock;
 581         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 582         if (rc)
 583                 goto out_lock;
 584         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 585         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 586 out_lock:
 587         unlock_dir(lower_dir_dentry);
 588         dput(lower_dentry);
 589         if (!dentry->d_inode)
 590                 d_drop(dentry);
 591         return rc;
 592 }
 593
 594 static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 595 {
 596         int rc;
 597         struct dentry *lower_dentry;
 598         struct dentry *lower_dir_dentry;
 599
 600         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 601         lower_dir_dentry = lock_parent(lower_dentry);
 602         rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
 603         if (rc || !lower_dentry->d_inode)
 604                 goto out;
 605         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 606         if (rc)
 607                 goto out;
 608         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 609         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 610         dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
 611 out:
 612         unlock_dir(lower_dir_dentry);
 613         if (!dentry->d_inode)
 614                 d_drop(dentry);
 615         return rc;
 616 }
 617
 618 static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
 619 {
 620         struct dentry *lower_dentry;
 621         struct dentry *lower_dir_dentry;
 622         int rc;
 623
 624         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 625         dget(dentry);
 626         lower_dir_dentry = lock_parent(lower_dentry);
 627         dget(lower_dentry);
 628         rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
 629         dput(lower_dentry);
 630         if (!rc)
 631                 d_delete(lower_dentry);
 632         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 633         dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
 634         unlock_dir(lower_dir_dentry);
 635         if (!rc)
 636                 d_drop(dentry);
 637         dput(dentry);
 638         return rc;
 639 }
 640
 641 static int
 642 ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
 643 {
 644         int rc;
 645         struct dentry *lower_dentry;
 646         struct dentry *lower_dir_dentry;
 647
 648         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 649         lower_dir_dentry = lock_parent(lower_dentry);
 650         rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
 651         if (rc || !lower_dentry->d_inode)
 652                 goto out;
 653         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 654         if (rc)
 655                 goto out;
 656         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 657         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 658 out:
 659         unlock_dir(lower_dir_dentry);
 660         if (!dentry->d_inode)
 661                 d_drop(dentry);
 662         return rc;
 663 }
 664
 665 static int
 666 ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 667                 struct inode *new_dir, struct dentry *new_dentry)
 668 {
 669         int rc;
 670         struct dentry *lower_old_dentry;
 671         struct dentry *lower_new_dentry;
 672         struct dentry *lower_old_dir_dentry;
 673         struct dentry *lower_new_dir_dentry;
 674         struct dentry *trap = NULL;
 675
 676         lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
 677         lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 678         dget(lower_old_dentry);
 679         dget(lower_new_dentry);
 680         lower_old_dir_dentry = dget_parent(lower_old_dentry);
 681         lower_new_dir_dentry = dget_parent(lower_new_dentry);
 682         trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
 683         /* source should not be ancestor of target */
 684         if (trap == lower_old_dentry) {
 685                 rc = -EINVAL;
 686                 goto out_lock;
 687         }
 688         /* target should not be ancestor of source */
 689         if (trap == lower_new_dentry) {
 690                 rc = -ENOTEMPTY;
 691                 goto out_lock;
 692         }
 693         rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
 694                         lower_new_dir_dentry->d_inode, lower_new_dentry);
 695         if (rc)
 696                 goto out_lock;
 697         fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
 698         if (new_dir != old_dir)
 699                 fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
 700 out_lock:
 701         unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
 702         dput(lower_new_dentry->d_parent);
 703         dput(lower_old_dentry->d_parent);
 704         dput(lower_new_dentry);
 705         dput(lower_old_dentry);
 706         return rc;
 707 }
 708
 709 static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf,
 710                                    size_t *bufsiz)
 711 {
 712         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 713         char *lower_buf;
 714         size_t lower_bufsiz = PATH_MAX;
 715         mm_segment_t old_fs;
 716         int rc;
 717
 718         lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
 719         if (!lower_buf) {
 720                 rc = -ENOMEM;
 721                 goto out;
 722         }
 723         old_fs = get_fs();
 724         set_fs(get_ds());
 725         rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
 726                                                    (char __user *)lower_buf,
 727                                                    lower_bufsiz);
 728         set_fs(old_fs);
 729         if (rc < 0)
 730                 goto out;
 731         lower_bufsiz = rc;
 732         rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry,
 733                                                   lower_buf, lower_bufsiz);
 734 out:
 735         kfree(lower_buf);
 736         return rc;
 737 }
 738
 739 static int
 740 ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
 741 {
 742         char *kbuf;
 743         size_t kbufsiz, copied;
 744         int rc;
 745
 746         rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz);
 747         if (rc)
 748                 goto out;
 749         copied = min_t(size_t, bufsiz, kbufsiz);
 750         rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied;
 751         kfree(kbuf);
 752         fsstack_copy_attr_atime(dentry->d_inode,
 753                                 ecryptfs_dentry_to_lower(dentry)->d_inode);
 754 out:
 755         return rc;
 756 }
 757
 758 static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 759 {
 760         char *buf;
 761         int len = PAGE_SIZE, rc;
 762         mm_segment_t old_fs;
 763
 764         /* Released in ecryptfs_put_link(); only release here on error */
 765         buf = kmalloc(len, GFP_KERNEL);
 766         if (!buf) {
 767                 buf = ERR_PTR(-ENOMEM);
 768                 goto out;
 769         }
 770         old_fs = get_fs();
 771         set_fs(get_ds());
 772         rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
 773         set_fs(old_fs);
 774         if (rc < 0) {
 775                 kfree(buf);
 776                 buf = ERR_PTR(rc);
 777         } else
 778                 buf[rc] = '\0';
 779 out:
 780         nd_set_link(nd, buf);
 781         return NULL;
 782 }
 783
 784 static void
 785 ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
 786 {
 787         char *buf = nd_get_link(nd);
 788         if (!IS_ERR(buf)) {
 789                 /* Free the char* */
 790                 kfree(buf);
 791         }
 792 }
 793
 794 /**
 795  * upper_size_to_lower_size
 796  * @crypt_stat: Crypt_stat associated with file
 797  * @upper_size: Size of the upper file
 798  *
 799  * Calculate the required size of the lower file based on the
 800  * specified size of the upper file. This calculation is based on the
 801  * number of headers in the underlying file and the extent size.
 802  *
 803  * Returns Calculated size of the lower file.
 804  */
 805 static loff_t
 806 upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
 807                          loff_t upper_size)
 808 {
 809         loff_t lower_size;
 810
 811         lower_size = ecryptfs_lower_header_size(crypt_stat);
 812         if (upper_size != 0) {
 813                 loff_t num_extents;
 814
 815                 num_extents = upper_size >> crypt_stat->extent_shift;
 816                 if (upper_size & ~crypt_stat->extent_mask)
 817                         num_extents++;
 818                 lower_size += (num_extents * crypt_stat->extent_size);
 819         }
 820         return lower_size;
 821 }
 822
 823 /**
 824  * truncate_upper
 825  * @dentry: The ecryptfs layer dentry
 826  * @ia: Address of the ecryptfs inode's attributes
 827  * @lower_ia: Address of the lower inode's attributes
 828  *
 829  * Function to handle truncations modifying the size of the file. Note
 830  * that the file sizes are interpolated. When expanding, we are simply
 831  * writing strings of 0's out. When truncating, we truncate the upper
 832  * inode and update the lower_ia according to the page index
 833  * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
 834  * the caller must use lower_ia in a call to notify_change() to perform
 835  * the truncation of the lower inode.
 836  *
 837  * Returns zero on success; non-zero otherwise
 838  */
 839 static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 840                           struct iattr *lower_ia)
 841 {
 842         int rc = 0;
 843         struct inode *inode = dentry->d_inode;
 844         struct ecryptfs_crypt_stat *crypt_stat;
 845         loff_t i_size = i_size_read(inode);
 846         loff_t lower_size_before_truncate;
 847         loff_t lower_size_after_truncate;
 848
 849         if (unlikely((ia->ia_size == i_size))) {
 850                 lower_ia->ia_valid &= ~ATTR_SIZE;
 851                 goto out;
 852         }
 853         crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
 854         /* Switch on growing or shrinking file */
 855         if (ia->ia_size > i_size) {
 856                 char zero[] = { 0x00 };
 857
 858                 lower_ia->ia_valid &= ~ATTR_SIZE;
 859                 /* Write a single 0 at the last position of the file;
 860                  * this triggers code that will fill in 0's throughout
 861                  * the intermediate portion of the previous end of the
 862                  * file and the new and of the file */
 863                 rc = ecryptfs_write(inode, zero,
 864                                     (ia->ia_size - 1), 1);
 865         } else { /* ia->ia_size < i_size_read(inode) */
 866                 /* We're chopping off all the pages down to the page
 867                  * in which ia->ia_size is located. Fill in the end of
 868                  * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to
 869                  * PAGE_CACHE_SIZE with zeros. */
 870                 size_t num_zeros = (PAGE_CACHE_SIZE
 871                                     - (ia->ia_size & ~PAGE_CACHE_MASK));
 872
 873                 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
 874                         rc = simple_setsize(inode, ia->ia_size);
 875                         if (rc)
 876                                 goto out;
 877                         lower_ia->ia_size = ia->ia_size;
 878                         lower_ia->ia_valid |= ATTR_SIZE;
 879                         goto out;
 880                 }
 881                 if (num_zeros) {
 882                         char *zeros_virt;
 883
 884                         zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
 885                         if (!zeros_virt) {
 886                                 rc = -ENOMEM;
 887                                 goto out;
 888                         }
 889                         rc = ecryptfs_write(inode, zeros_virt,
 890                                             ia->ia_size, num_zeros);
 891                         kfree(zeros_virt);
 892                         if (rc) {
 893                                 printk(KERN_ERR "Error attempting to zero out "
 894                                        "the remainder of the end page on "
 895                                        "reducing truncate; rc = [%d]\n", rc);
 896                                 goto out;
 897                         }
 898                 }
 899                 simple_setsize(inode, ia->ia_size);
 900                 rc = ecryptfs_write_inode_size_to_metadata(inode);
 901                 if (rc) {
 902                         printk(KERN_ERR "Problem with "
 903                                "ecryptfs_write_inode_size_to_metadata; "
 904                                "rc = [%d]\n", rc);
 905                         goto out;
 906                 }
 907                 /* We are reducing the size of the ecryptfs file, and need to
 908                  * know if we need to reduce the size of the lower file. */
 909                 lower_size_before_truncate =
 910                     upper_size_to_lower_size(crypt_stat, i_size);
 911                 lower_size_after_truncate =
 912                     upper_size_to_lower_size(crypt_stat, ia->ia_size);
 913                 if (lower_size_after_truncate < lower_size_before_truncate) {
 914                         lower_ia->ia_size = lower_size_after_truncate;
 915                         lower_ia->ia_valid |= ATTR_SIZE;
 916                 } else
 917                         lower_ia->ia_valid &= ~ATTR_SIZE;
 918         }
 919 out:
 920         return rc;
 921 }
 922
 923 /**
 924  * ecryptfs_truncate
 925  * @dentry: The ecryptfs layer dentry
 926  * @new_length: The length to expand the file to
 927  *
 928  * Simple function that handles the truncation of an eCryptfs inode and
 929  * its corresponding lower inode.
 930  *
 931  * Returns zero on success; non-zero otherwise
 932  */
 933 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
 934 {
 935         struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
 936         struct iattr lower_ia = { .ia_valid = 0 };
 937         int rc;
 938
 939         rc = truncate_upper(dentry, &ia, &lower_ia);
 940         if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
 941                 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 942
 943                 mutex_lock(&lower_dentry->d_inode->i_mutex);
 944                 rc = notify_change(lower_dentry, &lower_ia);
 945                 mutex_unlock(&lower_dentry->d_inode->i_mutex);
 946         }
 947         return rc;
 948 }
 949
 950 static int
 951 ecryptfs_permission(struct inode *inode, int mask)
 952 {
 953         return inode_permission(ecryptfs_inode_to_lower(inode), mask);
 954 }
 955
 956 /**
 957  * ecryptfs_setattr
 958  * @dentry: dentry handle to the inode to modify
 959  * @ia: Structure with flags of what to change and values
 960  *
 961  * Updates the metadata of an inode. If the update is to the size
 962  * i.e. truncation, then ecryptfs_truncate will handle the size modification
 963  * of both the ecryptfs inode and the lower inode.
 964  *
 965  * All other metadata changes will be passed right to the lower filesystem,
 966  * and we will just update our inode to look like the lower.
 967  */
 968 static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
 969 {
 970         int rc = 0;
 971         struct dentry *lower_dentry;
 972         struct iattr lower_ia;
 973         struct inode *inode;
 974         struct inode *lower_inode;
 975         struct ecryptfs_crypt_stat *crypt_stat;
 976
 977         crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
 978         if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
 979                 ecryptfs_init_crypt_stat(crypt_stat);
 980         inode = dentry->d_inode;
 981         lower_inode = ecryptfs_inode_to_lower(inode);
 982         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 983         mutex_lock(&crypt_stat->cs_mutex);
 984         if (S_ISDIR(dentry->d_inode->i_mode))
 985                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
 986         else if (S_ISREG(dentry->d_inode->i_mode)
 987                  && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
 988                      || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
 989                 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 990
 991                 mount_crypt_stat = &ecryptfs_superblock_to_private(
 992                         dentry->d_sb)->mount_crypt_stat;
 993                 rc = ecryptfs_read_metadata(dentry);
 994                 if (rc) {
 995                         if (!(mount_crypt_stat->flags
 996                               & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
 997                                 rc = -EIO;
 998                                 printk(KERN_WARNING "Either the lower file "
 999                                        "is not in a valid eCryptfs format, "
1000                                        "or the key could not be retrieved. "
1001                                        "Plaintext passthrough mode is not "
1002                                        "enabled; returning -EIO\n");
1003                                 mutex_unlock(&crypt_stat->cs_mutex);
1004                                 goto out;
1005                         }
1006                         rc = 0;
1007                         crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
1008                 }
1009         }
1010         mutex_unlock(&crypt_stat->cs_mutex);
1011         memcpy(&lower_ia, ia, sizeof(lower_ia));
1012         if (ia->ia_valid & ATTR_FILE)
1013                 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
1014         if (ia->ia_valid & ATTR_SIZE) {
1015                 rc = truncate_upper(dentry, ia, &lower_ia);
1016                 if (rc < 0)
1017                         goto out;
1018         }
1019
1020         /*
1021          * mode change is for clearing setuid/setgid bits. Allow lower fs
1022          * to interpret this in its own way.
1023          */
1024         if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
1025                 lower_ia.ia_valid &= ~ATTR_MODE;
1026
1027         mutex_lock(&lower_dentry->d_inode->i_mutex);
1028         rc = notify_change(lower_dentry, &lower_ia);
1029         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1030 out:
1031         fsstack_copy_attr_all(inode, lower_inode);
1032         return rc;
1033 }
1034
1035 int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
1036                           struct kstat *stat)
1037 {
1038         struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
1039         int rc = 0;
1040
1041         mount_crypt_stat = &ecryptfs_superblock_to_private(
1042                                                 dentry->d_sb)->mount_crypt_stat;
1043         generic_fillattr(dentry->d_inode, stat);
1044         if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
1045                 char *target;
1046                 size_t targetsiz;
1047
1048                 rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz);
1049                 if (!rc) {
1050                         kfree(target);
1051                         stat->size = targetsiz;
1052                 }
1053         }
1054         return rc;
1055 }
1056
1057 int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1058                      struct kstat *stat)
1059 {
1060         struct kstat lower_stat;
1061         int rc;
1062
1063         rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry),
1064                          ecryptfs_dentry_to_lower(dentry), &lower_stat);
1065         if (!rc) {
1066                 generic_fillattr(dentry->d_inode, stat);
1067                 stat->blocks = lower_stat.blocks;
1068         }
1069         return rc;
1070 }
1071
1072 int
1073 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
1074                   size_t size, int flags)
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->setxattr) {
1081                 rc = -EOPNOTSUPP;
1082                 goto out;
1083         }
1084         mutex_lock(&lower_dentry->d_inode->i_mutex);
1085         rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value,
1086                                                    size, flags);
1087         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1088 out:
1089         return rc;
1090 }
1091
1092 ssize_t
1093 ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
1094                         void *value, size_t size)
1095 {
1096         int rc = 0;
1097
1098         if (!lower_dentry->d_inode->i_op->getxattr) {
1099                 rc = -EOPNOTSUPP;
1100                 goto out;
1101         }
1102         mutex_lock(&lower_dentry->d_inode->i_mutex);
1103         rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
1104                                                    size);
1105         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1106 out:
1107         return rc;
1108 }
1109
1110 static ssize_t
1111 ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
1112                   size_t size)
1113 {
1114         return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
1115                                        value, size);
1116 }
1117
1118 static ssize_t
1119 ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1120 {
1121         int rc = 0;
1122         struct dentry *lower_dentry;
1123
1124         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1125         if (!lower_dentry->d_inode->i_op->listxattr) {
1126                 rc = -EOPNOTSUPP;
1127                 goto out;
1128         }
1129         mutex_lock(&lower_dentry->d_inode->i_mutex);
1130         rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
1131         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1132 out:
1133         return rc;
1134 }
1135
1136 static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
1137 {
1138         int rc = 0;
1139         struct dentry *lower_dentry;
1140
1141         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1142         if (!lower_dentry->d_inode->i_op->removexattr) {
1143                 rc = -EOPNOTSUPP;
1144                 goto out;
1145         }
1146         mutex_lock(&lower_dentry->d_inode->i_mutex);
1147         rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
1148         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1149 out:
1150         return rc;
1151 }
1152
1153 int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
1154 {
1155         if ((ecryptfs_inode_to_lower(inode)
1156              == (struct inode *)candidate_lower_inode))
1157                 return 1;
1158         else
1159                 return 0;
1160 }
1161
1162 int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
1163 {
1164         ecryptfs_init_inode(inode, (struct inode *)lower_inode);
1165         return 0;
1166 }
1167
1168 const struct inode_operations ecryptfs_symlink_iops = {
1169         .readlink = ecryptfs_readlink,
1170         .follow_link = ecryptfs_follow_link,
1171         .put_link = ecryptfs_put_link,
1172         .permission = ecryptfs_permission,
1173         .setattr = ecryptfs_setattr,
1174         .getattr = ecryptfs_getattr_link,
1175         .setxattr = ecryptfs_setxattr,
1176         .getxattr = ecryptfs_getxattr,
1177         .listxattr = ecryptfs_listxattr,
1178         .removexattr = ecryptfs_removexattr
1179 };
1180
1181 const struct inode_operations ecryptfs_dir_iops = {
1182         .create = ecryptfs_create,
1183         .lookup = ecryptfs_lookup,
1184         .link = ecryptfs_link,
1185         .unlink = ecryptfs_unlink,
1186         .symlink = ecryptfs_symlink,
1187         .mkdir = ecryptfs_mkdir,
1188         .rmdir = ecryptfs_rmdir,
1189         .mknod = ecryptfs_mknod,
1190         .rename = ecryptfs_rename,
1191         .permission = ecryptfs_permission,
1192         .setattr = ecryptfs_setattr,
1193         .setxattr = ecryptfs_setxattr,
1194         .getxattr = ecryptfs_getxattr,
1195         .listxattr = ecryptfs_listxattr,
1196         .removexattr = ecryptfs_removexattr
1197 };
1198
1199 const struct inode_operations ecryptfs_main_iops = {
1200         .permission = ecryptfs_permission,
1201         .setattr = ecryptfs_setattr,
1202         .getattr = ecryptfs_getattr,
1203         .setxattr = ecryptfs_setxattr,
1204         .getxattr = ecryptfs_getxattr,
1205         .listxattr = ecryptfs_listxattr,
1206         .removexattr = ecryptfs_removexattr
1207 };