fs/ecryptfs/inode.c

   1 /**
   2  * eCryptfs: Linux filesystem encryption layer
   3  *
   4  * Copyright (C) 1997-2004 Erez Zadok
   5  * Copyright (C) 2001-2004 Stony Brook University
   6  * Copyright (C) 2004-2007 International Business Machines Corp.
   7  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
   8  *              Michael C. Thompsion <mcthomps@us.ibm.com>
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License as
  12  * published by the Free Software Foundation; either version 2 of the
  13  * License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  23  * 02111-1307, USA.
  24  */
  25
  26 #include <linux/file.h>
  27 #include <linux/vmalloc.h>
  28 #include <linux/pagemap.h>
  29 #include <linux/dcache.h>
  30 #include <linux/namei.h>
  31 #include <linux/mount.h>
  32 #include <linux/crypto.h>
  33 #include <linux/fs_stack.h>
  34 #include <linux/slab.h>
  35 #include <linux/xattr.h>
  36 #include <asm/unaligned.h>
  37 #include "ecryptfs_kernel.h"
  38
  39 static struct dentry *lock_parent(struct dentry *dentry)
  40 {
  41         struct dentry *dir;
  42
  43         dir = dget_parent(dentry);
  44         mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT);
  45         return dir;
  46 }
  47
  48 static void unlock_dir(struct dentry *dir)
  49 {
  50         mutex_unlock(&dir->d_inode->i_mutex);
  51         dput(dir);
  52 }
  53
  54 /**
  55  * ecryptfs_create_underlying_file
  56  * @lower_dir_inode: inode of the parent in the lower fs of the new file
  57  * @dentry: New file's dentry
  58  * @mode: The mode of the new file
  59  * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
  60  *
  61  * Creates the file in the lower file system.
  62  *
  63  * Returns zero on success; non-zero on error condition
  64  */
  65 static int
  66 ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
  67                                 struct dentry *dentry, int mode,
  68                                 struct nameidata *nd)
  69 {
  70         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
  71         struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
  72         struct dentry *dentry_save;
  73         struct vfsmount *vfsmount_save;
  74         unsigned int flags_save;
  75         int rc;
  76
  77         dentry_save = nd->path.dentry;
  78         vfsmount_save = nd->path.mnt;
  79         flags_save = nd->flags;
  80         nd->path.dentry = lower_dentry;
  81         nd->path.mnt = lower_mnt;
  82         nd->flags &= ~LOOKUP_OPEN;
  83         rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
  84         nd->path.dentry = dentry_save;
  85         nd->path.mnt = vfsmount_save;
  86         nd->flags = flags_save;
  87         return rc;
  88 }
  89
  90 /**
  91  * ecryptfs_do_create
  92  * @directory_inode: inode of the new file's dentry's parent in ecryptfs
  93  * @ecryptfs_dentry: New file's dentry in ecryptfs
  94  * @mode: The mode of the new file
  95  * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
  96  *
  97  * Creates the underlying file and the eCryptfs inode which will link to
  98  * it. It will also update the eCryptfs directory inode to mimic the
  99  * stat of the lower directory inode.
 100  *
 101  * Returns zero on success; non-zero on error condition
 102  */
 103 static int
 104 ecryptfs_do_create(struct inode *directory_inode,
 105                    struct dentry *ecryptfs_dentry, int mode,
 106                    struct nameidata *nd)
 107 {
 108         int rc;
 109         struct dentry *lower_dentry;
 110         struct dentry *lower_dir_dentry;
 111
 112         lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
 113         lower_dir_dentry = lock_parent(lower_dentry);
 114         if (IS_ERR(lower_dir_dentry)) {
 115                 ecryptfs_printk(KERN_ERR, "Error locking directory of "
 116                                 "dentry\n");
 117                 rc = PTR_ERR(lower_dir_dentry);
 118                 goto out;
 119         }
 120         rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
 121                                              ecryptfs_dentry, mode, nd);
 122         if (rc) {
 123                 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
 124                        "rc = [%d]\n", __func__, rc);
 125                 goto out_lock;
 126         }
 127         rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
 128                                 directory_inode->i_sb, 0);
 129         if (rc) {
 130                 ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
 131                 goto out_lock;
 132         }
 133         fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
 134         fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
 135 out_lock:
 136         unlock_dir(lower_dir_dentry);
 137 out:
 138         return rc;
 139 }
 140
 141 /**
 142  * grow_file
 143  * @ecryptfs_dentry: the eCryptfs dentry
 144  *
 145  * This is the code which will grow the file to its correct size.
 146  */
 147 static int grow_file(struct dentry *ecryptfs_dentry)
 148 {
 149         struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
 150         char zero_virt[] = { 0x00 };
 151         int rc = 0;
 152
 153         rc = ecryptfs_write(ecryptfs_inode, zero_virt, 0, 1);
 154         i_size_write(ecryptfs_inode, 0);
 155         rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
 156         ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |=
 157                 ECRYPTFS_NEW_FILE;
 158         return rc;
 159 }
 160
 161 /**
 162  * ecryptfs_initialize_file
 163  *
 164  * Cause the file to be changed from a basic empty file to an ecryptfs
 165  * file with a header and first data page.
 166  *
 167  * Returns zero on success
 168  */
 169 static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
 170 {
 171         struct ecryptfs_crypt_stat *crypt_stat =
 172                 &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
 173         int rc = 0;
 174
 175         if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
 176                 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
 177                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
 178                 goto out;
 179         }
 180         crypt_stat->flags |= ECRYPTFS_NEW_FILE;
 181         ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
 182         rc = ecryptfs_new_file_context(ecryptfs_dentry);
 183         if (rc) {
 184                 ecryptfs_printk(KERN_ERR, "Error creating new file "
 185                                 "context; rc = [%d]\n", rc);
 186                 goto out;
 187         }
 188         if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
 189                 rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
 190                 if (rc) {
 191                         printk(KERN_ERR "%s: Error attempting to initialize "
 192                                "the persistent file for the dentry with name "
 193                                "[%s]; rc = [%d]\n", __func__,
 194                                ecryptfs_dentry->d_name.name, rc);
 195                         goto out;
 196                 }
 197         }
 198         rc = ecryptfs_write_metadata(ecryptfs_dentry);
 199         if (rc) {
 200                 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
 201                 goto out;
 202         }
 203         rc = grow_file(ecryptfs_dentry);
 204         if (rc)
 205                 printk(KERN_ERR "Error growing file; rc = [%d]\n", rc);
 206 out:
 207         return rc;
 208 }
 209
 210 /**
 211  * ecryptfs_create
 212  * @dir: The inode of the directory in which to create the file.
 213  * @dentry: The eCryptfs dentry
 214  * @mode: The mode of the new file.
 215  * @nd: nameidata
 216  *
 217  * Creates a new file.
 218  *
 219  * Returns zero on success; non-zero on error condition
 220  */
 221 static int
 222 ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
 223                 int mode, struct nameidata *nd)
 224 {
 225         int rc;
 226
 227         /* ecryptfs_do_create() calls ecryptfs_interpose() */
 228         rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd);
 229         if (unlikely(rc)) {
 230                 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
 231                                 "lower filesystem\n");
 232                 goto out;
 233         }
 234         /* At this point, a file exists on "disk"; we need to make sure
 235          * that this on disk file is prepared to be an ecryptfs file */
 236         rc = ecryptfs_initialize_file(ecryptfs_dentry);
 237 out:
 238         return rc;
 239 }
 240
 241 /**
 242  * ecryptfs_lookup_and_interpose_lower - Perform a lookup
 243  */
 244 int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
 245                                         struct dentry *lower_dentry,
 246                                         struct inode *ecryptfs_dir_inode,
 247                                         struct nameidata *ecryptfs_nd)
 248 {
 249         struct dentry *lower_dir_dentry;
 250         struct vfsmount *lower_mnt;
 251         struct inode *lower_inode;
 252         struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 253         struct ecryptfs_crypt_stat *crypt_stat;
 254         char *page_virt = NULL;
 255         u64 file_size;
 256         int rc = 0;
 257
 258         lower_dir_dentry = lower_dentry->d_parent;
 259         lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
 260                                    ecryptfs_dentry->d_parent));
 261         lower_inode = lower_dentry->d_inode;
 262         fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode);
 263         BUG_ON(!lower_dentry->d_count);
 264         ecryptfs_set_dentry_private(ecryptfs_dentry,
 265                                     kmem_cache_alloc(ecryptfs_dentry_info_cache,
 266                                                      GFP_KERNEL));
 267         if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) {
 268                 rc = -ENOMEM;
 269                 printk(KERN_ERR "%s: Out of memory whilst attempting "
 270                        "to allocate ecryptfs_dentry_info struct\n",
 271                         __func__);
 272                 goto out_put;
 273         }
 274         ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry);
 275         ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt);
 276         if (!lower_dentry->d_inode) {
 277                 /* We want to add because we couldn't find in lower */
 278                 d_add(ecryptfs_dentry, NULL);
 279                 goto out;
 280         }
 281         rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
 282                                 ecryptfs_dir_inode->i_sb,
 283                                 ECRYPTFS_INTERPOSE_FLAG_D_ADD);
 284         if (rc) {
 285                 printk(KERN_ERR "%s: Error interposing; rc = [%d]\n",
 286                        __func__, rc);
 287                 goto out;
 288         }
 289         if (S_ISDIR(lower_inode->i_mode))
 290                 goto out;
 291         if (S_ISLNK(lower_inode->i_mode))
 292                 goto out;
 293         if (special_file(lower_inode->i_mode))
 294                 goto out;
 295         if (!ecryptfs_nd)
 296                 goto out;
 297         /* Released in this function */
 298         page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER);
 299         if (!page_virt) {
 300                 printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n",
 301                        __func__);
 302                 rc = -ENOMEM;
 303                 goto out;
 304         }
 305         if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) {
 306                 rc = ecryptfs_init_persistent_file(ecryptfs_dentry);
 307                 if (rc) {
 308                         printk(KERN_ERR "%s: Error attempting to initialize "
 309                                "the persistent file for the dentry with name "
 310                                "[%s]; rc = [%d]\n", __func__,
 311                                ecryptfs_dentry->d_name.name, rc);
 312                         goto out_free_kmem;
 313                 }
 314         }
 315         crypt_stat = &ecryptfs_inode_to_private(
 316                                         ecryptfs_dentry->d_inode)->crypt_stat;
 317         /* TODO: lock for crypt_stat comparison */
 318         if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
 319                         ecryptfs_set_default_sizes(crypt_stat);
 320         rc = ecryptfs_read_and_validate_header_region(page_virt,
 321                                                       ecryptfs_dentry->d_inode);
 322         if (rc) {
 323                 memset(page_virt, 0, PAGE_CACHE_SIZE);
 324                 rc = ecryptfs_read_and_validate_xattr_region(page_virt,
 325                                                              ecryptfs_dentry);
 326                 if (rc) {
 327                         rc = 0;
 328                         goto out_free_kmem;
 329                 }
 330                 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
 331         }
 332         mount_crypt_stat = &ecryptfs_superblock_to_private(
 333                 ecryptfs_dentry->d_sb)->mount_crypt_stat;
 334         if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
 335                 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
 336                         file_size = (crypt_stat->metadata_size
 337                                      + i_size_read(lower_dentry->d_inode));
 338                 else
 339                         file_size = i_size_read(lower_dentry->d_inode);
 340         } else {
 341                 file_size = get_unaligned_be64(page_virt);
 342         }
 343         i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size);
 344 out_free_kmem:
 345         kmem_cache_free(ecryptfs_header_cache_2, page_virt);
 346         goto out;
 347 out_put:
 348         dput(lower_dentry);
 349         mntput(lower_mnt);
 350         d_drop(ecryptfs_dentry);
 351 out:
 352         return rc;
 353 }
 354
 355 /**
 356  * ecryptfs_new_lower_dentry
 357  * @name: The name of the new dentry.
 358  * @lower_dir_dentry: Parent directory of the new dentry.
 359  * @nd: nameidata from last lookup.
 360  *
 361  * Create a new dentry or get it from lower parent dir.
 362  */
 363 static struct dentry *
 364 ecryptfs_new_lower_dentry(struct qstr *name, struct dentry *lower_dir_dentry,
 365                           struct nameidata *nd)
 366 {
 367         struct dentry *new_dentry;
 368         struct dentry *tmp;
 369         struct inode *lower_dir_inode;
 370
 371         lower_dir_inode = lower_dir_dentry->d_inode;
 372
 373         tmp = d_alloc(lower_dir_dentry, name);
 374         if (!tmp)
 375                 return ERR_PTR(-ENOMEM);
 376
 377         mutex_lock(&lower_dir_inode->i_mutex);
 378         new_dentry = lower_dir_inode->i_op->lookup(lower_dir_inode, tmp, nd);
 379         mutex_unlock(&lower_dir_inode->i_mutex);
 380
 381         if (!new_dentry)
 382                 new_dentry = tmp;
 383         else
 384                 dput(tmp);
 385
 386         return new_dentry;
 387 }
 388
 389
 390 /**
 391  * ecryptfs_lookup_one_lower
 392  * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
 393  * @lower_dir_dentry: lower parent directory
 394  * @name: lower file name
 395  *
 396  * Get the lower dentry from vfs. If lower dentry does not exist yet,
 397  * create it.
 398  */
 399 static struct dentry *
 400 ecryptfs_lookup_one_lower(struct dentry *ecryptfs_dentry,
 401                           struct dentry *lower_dir_dentry, struct qstr *name)
 402 {
 403         struct nameidata nd;
 404         struct vfsmount *lower_mnt;
 405         int err;
 406
 407         lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
 408                                     ecryptfs_dentry->d_parent));
 409         err = vfs_path_lookup(lower_dir_dentry, lower_mnt, name->name , 0, &nd);
 410         mntput(lower_mnt);
 411
 412         if (!err) {
 413                 /* we dont need the mount */
 414                 mntput(nd.path.mnt);
 415                 return nd.path.dentry;
 416         }
 417         if (err != -ENOENT)
 418                 return ERR_PTR(err);
 419
 420         /* create a new lower dentry */
 421         return ecryptfs_new_lower_dentry(name, lower_dir_dentry, &nd);
 422 }
 423
 424 /**
 425  * ecryptfs_lookup
 426  * @ecryptfs_dir_inode: The eCryptfs directory inode
 427  * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
 428  * @ecryptfs_nd: nameidata; may be NULL
 429  *
 430  * Find a file on disk. If the file does not exist, then we'll add it to the
 431  * dentry cache and continue on to read it from the disk.
 432  */
 433 static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
 434                                       struct dentry *ecryptfs_dentry,
 435                                       struct nameidata *ecryptfs_nd)
 436 {
 437         char *encrypted_and_encoded_name = NULL;
 438         size_t encrypted_and_encoded_name_size;
 439         struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
 440         struct dentry *lower_dir_dentry, *lower_dentry;
 441         struct qstr lower_name;
 442         int rc = 0;
 443
 444         d_set_d_op(ecryptfs_dentry, &ecryptfs_dops);
 445         if ((ecryptfs_dentry->d_name.len == 1
 446              && !strcmp(ecryptfs_dentry->d_name.name, "."))
 447             || (ecryptfs_dentry->d_name.len == 2
 448                 && !strcmp(ecryptfs_dentry->d_name.name, ".."))) {
 449                 goto out_d_drop;
 450         }
 451         lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
 452         lower_name.name = ecryptfs_dentry->d_name.name;
 453         lower_name.len = ecryptfs_dentry->d_name.len;
 454         lower_name.hash = ecryptfs_dentry->d_name.hash;
 455         if (lower_dir_dentry->d_op && lower_dir_dentry->d_op->d_hash) {
 456                 rc = lower_dir_dentry->d_op->d_hash(lower_dir_dentry,
 457                                 lower_dir_dentry->d_inode, &lower_name);
 458                 if (rc < 0)
 459                         goto out_d_drop;
 460         }
 461         lower_dentry = ecryptfs_lookup_one_lower(ecryptfs_dentry,
 462                                                  lower_dir_dentry, &lower_name);
 463         if (IS_ERR(lower_dentry)) {
 464                 rc = PTR_ERR(lower_dentry);
 465                 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_lower() returned "
 466                                 "[%d] on lower_dentry = [%s]\n", __func__, rc,
 467                                 encrypted_and_encoded_name);
 468                 goto out_d_drop;
 469         }
 470         if (lower_dentry->d_inode)
 471                 goto lookup_and_interpose;
 472         mount_crypt_stat = &ecryptfs_superblock_to_private(
 473                                 ecryptfs_dentry->d_sb)->mount_crypt_stat;
 474         if (!(mount_crypt_stat
 475             && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
 476                 goto lookup_and_interpose;
 477         dput(lower_dentry);
 478         rc = ecryptfs_encrypt_and_encode_filename(
 479                 &encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
 480                 NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name,
 481                 ecryptfs_dentry->d_name.len);
 482         if (rc) {
 483                 printk(KERN_ERR "%s: Error attempting to encrypt and encode "
 484                        "filename; rc = [%d]\n", __func__, rc);
 485                 goto out_d_drop;
 486         }
 487         lower_name.name = encrypted_and_encoded_name;
 488         lower_name.len = encrypted_and_encoded_name_size;
 489         lower_name.hash = full_name_hash(lower_name.name, lower_name.len);
 490         if (lower_dir_dentry->d_op && lower_dir_dentry->d_op->d_hash) {
 491                 rc = lower_dir_dentry->d_op->d_hash(lower_dir_dentry,
 492                                 lower_dir_dentry->d_inode, &lower_name);
 493                 if (rc < 0)
 494                         goto out_d_drop;
 495         }
 496         lower_dentry = ecryptfs_lookup_one_lower(ecryptfs_dentry,
 497                                                  lower_dir_dentry, &lower_name);
 498         if (IS_ERR(lower_dentry)) {
 499                 rc = PTR_ERR(lower_dentry);
 500                 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_lower() returned "
 501                                 "[%d] on lower_dentry = [%s]\n", __func__, rc,
 502                                 encrypted_and_encoded_name);
 503                 goto out_d_drop;
 504         }
 505 lookup_and_interpose:
 506         rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry,
 507                                                  ecryptfs_dir_inode,
 508                                                  ecryptfs_nd);
 509         goto out;
 510 out_d_drop:
 511         d_drop(ecryptfs_dentry);
 512 out:
 513         kfree(encrypted_and_encoded_name);
 514         return ERR_PTR(rc);
 515 }
 516
 517 static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
 518                          struct dentry *new_dentry)
 519 {
 520         struct dentry *lower_old_dentry;
 521         struct dentry *lower_new_dentry;
 522         struct dentry *lower_dir_dentry;
 523         u64 file_size_save;
 524         int rc;
 525
 526         file_size_save = i_size_read(old_dentry->d_inode);
 527         lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
 528         lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 529         dget(lower_old_dentry);
 530         dget(lower_new_dentry);
 531         lower_dir_dentry = lock_parent(lower_new_dentry);
 532         rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
 533                       lower_new_dentry);
 534         if (rc || !lower_new_dentry->d_inode)
 535                 goto out_lock;
 536         rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
 537         if (rc)
 538                 goto out_lock;
 539         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 540         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 541         old_dentry->d_inode->i_nlink =
 542                 ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
 543         i_size_write(new_dentry->d_inode, file_size_save);
 544 out_lock:
 545         unlock_dir(lower_dir_dentry);
 546         dput(lower_new_dentry);
 547         dput(lower_old_dentry);
 548         return rc;
 549 }
 550
 551 static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
 552 {
 553         int rc = 0;
 554         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 555         struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
 556         struct dentry *lower_dir_dentry;
 557
 558         dget(lower_dentry);
 559         lower_dir_dentry = lock_parent(lower_dentry);
 560         rc = vfs_unlink(lower_dir_inode, lower_dentry);
 561         if (rc) {
 562                 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
 563                 goto out_unlock;
 564         }
 565         fsstack_copy_attr_times(dir, lower_dir_inode);
 566         dentry->d_inode->i_nlink =
 567                 ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink;
 568         dentry->d_inode->i_ctime = dir->i_ctime;
 569         d_drop(dentry);
 570 out_unlock:
 571         unlock_dir(lower_dir_dentry);
 572         dput(lower_dentry);
 573         return rc;
 574 }
 575
 576 static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
 577                             const char *symname)
 578 {
 579         int rc;
 580         struct dentry *lower_dentry;
 581         struct dentry *lower_dir_dentry;
 582         char *encoded_symname;
 583         size_t encoded_symlen;
 584         struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
 585
 586         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 587         dget(lower_dentry);
 588         lower_dir_dentry = lock_parent(lower_dentry);
 589         mount_crypt_stat = &ecryptfs_superblock_to_private(
 590                 dir->i_sb)->mount_crypt_stat;
 591         rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
 592                                                   &encoded_symlen,
 593                                                   NULL,
 594                                                   mount_crypt_stat, symname,
 595                                                   strlen(symname));
 596         if (rc)
 597                 goto out_lock;
 598         rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
 599                          encoded_symname);
 600         kfree(encoded_symname);
 601         if (rc || !lower_dentry->d_inode)
 602                 goto out_lock;
 603         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 604         if (rc)
 605                 goto out_lock;
 606         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 607         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 608 out_lock:
 609         unlock_dir(lower_dir_dentry);
 610         dput(lower_dentry);
 611         if (!dentry->d_inode)
 612                 d_drop(dentry);
 613         return rc;
 614 }
 615
 616 static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 617 {
 618         int rc;
 619         struct dentry *lower_dentry;
 620         struct dentry *lower_dir_dentry;
 621
 622         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 623         lower_dir_dentry = lock_parent(lower_dentry);
 624         rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
 625         if (rc || !lower_dentry->d_inode)
 626                 goto out;
 627         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 628         if (rc)
 629                 goto out;
 630         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 631         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 632         dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
 633 out:
 634         unlock_dir(lower_dir_dentry);
 635         if (!dentry->d_inode)
 636                 d_drop(dentry);
 637         return rc;
 638 }
 639
 640 static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
 641 {
 642         struct dentry *lower_dentry;
 643         struct dentry *lower_dir_dentry;
 644         int rc;
 645
 646         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 647         dget(dentry);
 648         lower_dir_dentry = lock_parent(lower_dentry);
 649         dget(lower_dentry);
 650         rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
 651         dput(lower_dentry);
 652         if (!rc)
 653                 d_delete(lower_dentry);
 654         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 655         dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
 656         unlock_dir(lower_dir_dentry);
 657         if (!rc)
 658                 d_drop(dentry);
 659         dput(dentry);
 660         return rc;
 661 }
 662
 663 static int
 664 ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
 665 {
 666         int rc;
 667         struct dentry *lower_dentry;
 668         struct dentry *lower_dir_dentry;
 669
 670         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 671         lower_dir_dentry = lock_parent(lower_dentry);
 672         rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
 673         if (rc || !lower_dentry->d_inode)
 674                 goto out;
 675         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 676         if (rc)
 677                 goto out;
 678         fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
 679         fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 680 out:
 681         unlock_dir(lower_dir_dentry);
 682         if (!dentry->d_inode)
 683                 d_drop(dentry);
 684         return rc;
 685 }
 686
 687 static int
 688 ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 689                 struct inode *new_dir, struct dentry *new_dentry)
 690 {
 691         int rc;
 692         struct dentry *lower_old_dentry;
 693         struct dentry *lower_new_dentry;
 694         struct dentry *lower_old_dir_dentry;
 695         struct dentry *lower_new_dir_dentry;
 696         struct dentry *trap = NULL;
 697
 698         lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
 699         lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 700         dget(lower_old_dentry);
 701         dget(lower_new_dentry);
 702         lower_old_dir_dentry = dget_parent(lower_old_dentry);
 703         lower_new_dir_dentry = dget_parent(lower_new_dentry);
 704         trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
 705         /* source should not be ancestor of target */
 706         if (trap == lower_old_dentry) {
 707                 rc = -EINVAL;
 708                 goto out_lock;
 709         }
 710         /* target should not be ancestor of source */
 711         if (trap == lower_new_dentry) {
 712                 rc = -ENOTEMPTY;
 713                 goto out_lock;
 714         }
 715         rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
 716                         lower_new_dir_dentry->d_inode, lower_new_dentry);
 717         if (rc)
 718                 goto out_lock;
 719         fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
 720         if (new_dir != old_dir)
 721                 fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
 722 out_lock:
 723         unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
 724         dput(lower_new_dentry->d_parent);
 725         dput(lower_old_dentry->d_parent);
 726         dput(lower_new_dentry);
 727         dput(lower_old_dentry);
 728         return rc;
 729 }
 730
 731 static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf,
 732                                    size_t *bufsiz)
 733 {
 734         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 735         char *lower_buf;
 736         size_t lower_bufsiz = PATH_MAX;
 737         mm_segment_t old_fs;
 738         int rc;
 739
 740         lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
 741         if (!lower_buf) {
 742                 rc = -ENOMEM;
 743                 goto out;
 744         }
 745         old_fs = get_fs();
 746         set_fs(get_ds());
 747         rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
 748                                                    (char __user *)lower_buf,
 749                                                    lower_bufsiz);
 750         set_fs(old_fs);
 751         if (rc < 0)
 752                 goto out;
 753         lower_bufsiz = rc;
 754         rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry,
 755                                                   lower_buf, lower_bufsiz);
 756 out:
 757         kfree(lower_buf);
 758         return rc;
 759 }
 760
 761 static int
 762 ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
 763 {
 764         char *kbuf;
 765         size_t kbufsiz, copied;
 766         int rc;
 767
 768         rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz);
 769         if (rc)
 770                 goto out;
 771         copied = min_t(size_t, bufsiz, kbufsiz);
 772         rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied;
 773         kfree(kbuf);
 774         fsstack_copy_attr_atime(dentry->d_inode,
 775                                 ecryptfs_dentry_to_lower(dentry)->d_inode);
 776 out:
 777         return rc;
 778 }
 779
 780 static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 781 {
 782         char *buf;
 783         int len = PAGE_SIZE, rc;
 784         mm_segment_t old_fs;
 785
 786         /* Released in ecryptfs_put_link(); only release here on error */
 787         buf = kmalloc(len, GFP_KERNEL);
 788         if (!buf) {
 789                 buf = ERR_PTR(-ENOMEM);
 790                 goto out;
 791         }
 792         old_fs = get_fs();
 793         set_fs(get_ds());
 794         rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
 795         set_fs(old_fs);
 796         if (rc < 0) {
 797                 kfree(buf);
 798                 buf = ERR_PTR(rc);
 799         } else
 800                 buf[rc] = '\0';
 801 out:
 802         nd_set_link(nd, buf);
 803         return NULL;
 804 }
 805
 806 static void
 807 ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
 808 {
 809         char *buf = nd_get_link(nd);
 810         if (!IS_ERR(buf)) {
 811                 /* Free the char* */
 812                 kfree(buf);
 813         }
 814 }
 815
 816 /**
 817  * upper_size_to_lower_size
 818  * @crypt_stat: Crypt_stat associated with file
 819  * @upper_size: Size of the upper file
 820  *
 821  * Calculate the required size of the lower file based on the
 822  * specified size of the upper file. This calculation is based on the
 823  * number of headers in the underlying file and the extent size.
 824  *
 825  * Returns Calculated size of the lower file.
 826  */
 827 static loff_t
 828 upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
 829                          loff_t upper_size)
 830 {
 831         loff_t lower_size;
 832
 833         lower_size = ecryptfs_lower_header_size(crypt_stat);
 834         if (upper_size != 0) {
 835                 loff_t num_extents;
 836
 837                 num_extents = upper_size >> crypt_stat->extent_shift;
 838                 if (upper_size & ~crypt_stat->extent_mask)
 839                         num_extents++;
 840                 lower_size += (num_extents * crypt_stat->extent_size);
 841         }
 842         return lower_size;
 843 }
 844
 845 /**
 846  * truncate_upper
 847  * @dentry: The ecryptfs layer dentry
 848  * @ia: Address of the ecryptfs inode's attributes
 849  * @lower_ia: Address of the lower inode's attributes
 850  *
 851  * Function to handle truncations modifying the size of the file. Note
 852  * that the file sizes are interpolated. When expanding, we are simply
 853  * writing strings of 0's out. When truncating, we truncate the upper
 854  * inode and update the lower_ia according to the page index
 855  * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
 856  * the caller must use lower_ia in a call to notify_change() to perform
 857  * the truncation of the lower inode.
 858  *
 859  * Returns zero on success; non-zero otherwise
 860  */
 861 static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 862                           struct iattr *lower_ia)
 863 {
 864         int rc = 0;
 865         struct inode *inode = dentry->d_inode;
 866         struct ecryptfs_crypt_stat *crypt_stat;
 867         loff_t i_size = i_size_read(inode);
 868         loff_t lower_size_before_truncate;
 869         loff_t lower_size_after_truncate;
 870
 871         if (unlikely((ia->ia_size == i_size))) {
 872                 lower_ia->ia_valid &= ~ATTR_SIZE;
 873                 goto out;
 874         }
 875         crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
 876         /* Switch on growing or shrinking file */
 877         if (ia->ia_size > i_size) {
 878                 char zero[] = { 0x00 };
 879
 880                 lower_ia->ia_valid &= ~ATTR_SIZE;
 881                 /* Write a single 0 at the last position of the file;
 882                  * this triggers code that will fill in 0's throughout
 883                  * the intermediate portion of the previous end of the
 884                  * file and the new and of the file */
 885                 rc = ecryptfs_write(inode, zero,
 886                                     (ia->ia_size - 1), 1);
 887         } else { /* ia->ia_size < i_size_read(inode) */
 888                 /* We're chopping off all the pages down to the page
 889                  * in which ia->ia_size is located. Fill in the end of
 890                  * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to
 891                  * PAGE_CACHE_SIZE with zeros. */
 892                 size_t num_zeros = (PAGE_CACHE_SIZE
 893                                     - (ia->ia_size & ~PAGE_CACHE_MASK));
 894
 895
 896                 /*
 897                  * XXX(truncate) this should really happen at the begginning
 898                  * of ->setattr.  But the code is too messy to that as part
 899                  * of a larger patch.  ecryptfs is also totally missing out
 900                  * on the inode_change_ok check at the beginning of
 901                  * ->setattr while would include this.
 902                  */
 903                 rc = inode_newsize_ok(inode, ia->ia_size);
 904                 if (rc)
 905                         goto out;
 906
 907                 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
 908                         truncate_setsize(inode, ia->ia_size);
 909                         lower_ia->ia_size = ia->ia_size;
 910                         lower_ia->ia_valid |= ATTR_SIZE;
 911                         goto out;
 912                 }
 913                 if (num_zeros) {
 914                         char *zeros_virt;
 915
 916                         zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
 917                         if (!zeros_virt) {
 918                                 rc = -ENOMEM;
 919                                 goto out;
 920                         }
 921                         rc = ecryptfs_write(inode, zeros_virt,
 922                                             ia->ia_size, num_zeros);
 923                         kfree(zeros_virt);
 924                         if (rc) {
 925                                 printk(KERN_ERR "Error attempting to zero out "
 926                                        "the remainder of the end page on "
 927                                        "reducing truncate; rc = [%d]\n", rc);
 928                                 goto out;
 929                         }
 930                 }
 931                 truncate_setsize(inode, ia->ia_size);
 932                 rc = ecryptfs_write_inode_size_to_metadata(inode);
 933                 if (rc) {
 934                         printk(KERN_ERR "Problem with "
 935                                "ecryptfs_write_inode_size_to_metadata; "
 936                                "rc = [%d]\n", rc);
 937                         goto out;
 938                 }
 939                 /* We are reducing the size of the ecryptfs file, and need to
 940                  * know if we need to reduce the size of the lower file. */
 941                 lower_size_before_truncate =
 942                     upper_size_to_lower_size(crypt_stat, i_size);
 943                 lower_size_after_truncate =
 944                     upper_size_to_lower_size(crypt_stat, ia->ia_size);
 945                 if (lower_size_after_truncate < lower_size_before_truncate) {
 946                         lower_ia->ia_size = lower_size_after_truncate;
 947                         lower_ia->ia_valid |= ATTR_SIZE;
 948                 } else
 949                         lower_ia->ia_valid &= ~ATTR_SIZE;
 950         }
 951 out:
 952         return rc;
 953 }
 954
 955 /**
 956  * ecryptfs_truncate
 957  * @dentry: The ecryptfs layer dentry
 958  * @new_length: The length to expand the file to
 959  *
 960  * Simple function that handles the truncation of an eCryptfs inode and
 961  * its corresponding lower inode.
 962  *
 963  * Returns zero on success; non-zero otherwise
 964  */
 965 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
 966 {
 967         struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
 968         struct iattr lower_ia = { .ia_valid = 0 };
 969         int rc;
 970
 971         rc = truncate_upper(dentry, &ia, &lower_ia);
 972         if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
 973                 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 974
 975                 mutex_lock(&lower_dentry->d_inode->i_mutex);
 976                 rc = notify_change(lower_dentry, &lower_ia);
 977                 mutex_unlock(&lower_dentry->d_inode->i_mutex);
 978         }
 979         return rc;
 980 }
 981
 982 static int
 983 ecryptfs_permission(struct inode *inode, int mask, unsigned int flags)
 984 {
 985         if (flags & IPERM_FLAG_RCU)
 986                 return -ECHILD;
 987         return inode_permission(ecryptfs_inode_to_lower(inode), mask);
 988 }
 989
 990 /**
 991  * ecryptfs_setattr
 992  * @dentry: dentry handle to the inode to modify
 993  * @ia: Structure with flags of what to change and values
 994  *
 995  * Updates the metadata of an inode. If the update is to the size
 996  * i.e. truncation, then ecryptfs_truncate will handle the size modification
 997  * of both the ecryptfs inode and the lower inode.
 998  *
 999  * All other metadata changes will be passed right to the lower filesystem,
1000  * and we will just update our inode to look like the lower.
1001  */
1002 static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
1003 {
1004         int rc = 0;
1005         struct dentry *lower_dentry;
1006         struct iattr lower_ia;
1007         struct inode *inode;
1008         struct inode *lower_inode;
1009         struct ecryptfs_crypt_stat *crypt_stat;
1010
1011         crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
1012         if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
1013                 ecryptfs_init_crypt_stat(crypt_stat);
1014         inode = dentry->d_inode;
1015         lower_inode = ecryptfs_inode_to_lower(inode);
1016         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1017         mutex_lock(&crypt_stat->cs_mutex);
1018         if (S_ISDIR(dentry->d_inode->i_mode))
1019                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
1020         else if (S_ISREG(dentry->d_inode->i_mode)
1021                  && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
1022                      || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
1023                 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
1024
1025                 mount_crypt_stat = &ecryptfs_superblock_to_private(
1026                         dentry->d_sb)->mount_crypt_stat;
1027                 rc = ecryptfs_read_metadata(dentry);
1028                 if (rc) {
1029                         if (!(mount_crypt_stat->flags
1030                               & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
1031                                 rc = -EIO;
1032                                 printk(KERN_WARNING "Either the lower file "
1033                                        "is not in a valid eCryptfs format, "
1034                                        "or the key could not be retrieved. "
1035                                        "Plaintext passthrough mode is not "
1036                                        "enabled; returning -EIO\n");
1037                                 mutex_unlock(&crypt_stat->cs_mutex);
1038                                 goto out;
1039                         }
1040                         rc = 0;
1041                         crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
1042                 }
1043         }
1044         mutex_unlock(&crypt_stat->cs_mutex);
1045         memcpy(&lower_ia, ia, sizeof(lower_ia));
1046         if (ia->ia_valid & ATTR_FILE)
1047                 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
1048         if (ia->ia_valid & ATTR_SIZE) {
1049                 rc = truncate_upper(dentry, ia, &lower_ia);
1050                 if (rc < 0)
1051                         goto out;
1052         }
1053
1054         /*
1055          * mode change is for clearing setuid/setgid bits. Allow lower fs
1056          * to interpret this in its own way.
1057          */
1058         if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
1059                 lower_ia.ia_valid &= ~ATTR_MODE;
1060
1061         mutex_lock(&lower_dentry->d_inode->i_mutex);
1062         rc = notify_change(lower_dentry, &lower_ia);
1063         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1064 out:
1065         fsstack_copy_attr_all(inode, lower_inode);
1066         return rc;
1067 }
1068
1069 int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
1070                           struct kstat *stat)
1071 {
1072         struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
1073         int rc = 0;
1074
1075         mount_crypt_stat = &ecryptfs_superblock_to_private(
1076                                                 dentry->d_sb)->mount_crypt_stat;
1077         generic_fillattr(dentry->d_inode, stat);
1078         if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
1079                 char *target;
1080                 size_t targetsiz;
1081
1082                 rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz);
1083                 if (!rc) {
1084                         kfree(target);
1085                         stat->size = targetsiz;
1086                 }
1087         }
1088         return rc;
1089 }
1090
1091 int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1092                      struct kstat *stat)
1093 {
1094         struct kstat lower_stat;
1095         int rc;
1096
1097         rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry),
1098                          ecryptfs_dentry_to_lower(dentry), &lower_stat);
1099         if (!rc) {
1100                 generic_fillattr(dentry->d_inode, stat);
1101                 stat->blocks = lower_stat.blocks;
1102         }
1103         return rc;
1104 }
1105
1106 int
1107 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
1108                   size_t size, int flags)
1109 {
1110         int rc = 0;
1111         struct dentry *lower_dentry;
1112
1113         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1114         if (!lower_dentry->d_inode->i_op->setxattr) {
1115                 rc = -EOPNOTSUPP;
1116                 goto out;
1117         }
1118
1119         rc = vfs_setxattr(lower_dentry, name, value, size, flags);
1120 out:
1121         return rc;
1122 }
1123
1124 ssize_t
1125 ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
1126                         void *value, size_t size)
1127 {
1128         int rc = 0;
1129
1130         if (!lower_dentry->d_inode->i_op->getxattr) {
1131                 rc = -EOPNOTSUPP;
1132                 goto out;
1133         }
1134         mutex_lock(&lower_dentry->d_inode->i_mutex);
1135         rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
1136                                                    size);
1137         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1138 out:
1139         return rc;
1140 }
1141
1142 static ssize_t
1143 ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
1144                   size_t size)
1145 {
1146         return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
1147                                        value, size);
1148 }
1149
1150 static ssize_t
1151 ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1152 {
1153         int rc = 0;
1154         struct dentry *lower_dentry;
1155
1156         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1157         if (!lower_dentry->d_inode->i_op->listxattr) {
1158                 rc = -EOPNOTSUPP;
1159                 goto out;
1160         }
1161         mutex_lock(&lower_dentry->d_inode->i_mutex);
1162         rc = lower_dentry->d_inode->i_op->listxattr(lower_dentry, list, size);
1163         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1164 out:
1165         return rc;
1166 }
1167
1168 static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
1169 {
1170         int rc = 0;
1171         struct dentry *lower_dentry;
1172
1173         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1174         if (!lower_dentry->d_inode->i_op->removexattr) {
1175                 rc = -EOPNOTSUPP;
1176                 goto out;
1177         }
1178         mutex_lock(&lower_dentry->d_inode->i_mutex);
1179         rc = lower_dentry->d_inode->i_op->removexattr(lower_dentry, name);
1180         mutex_unlock(&lower_dentry->d_inode->i_mutex);
1181 out:
1182         return rc;
1183 }
1184
1185 int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
1186 {
1187         if ((ecryptfs_inode_to_lower(inode)
1188              == (struct inode *)candidate_lower_inode))
1189                 return 1;
1190         else
1191                 return 0;
1192 }
1193
1194 int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
1195 {
1196         ecryptfs_init_inode(inode, (struct inode *)lower_inode);
1197         return 0;
1198 }
1199
1200 const struct inode_operations ecryptfs_symlink_iops = {
1201         .readlink = ecryptfs_readlink,
1202         .follow_link = ecryptfs_follow_link,
1203         .put_link = ecryptfs_put_link,
1204         .permission = ecryptfs_permission,
1205         .setattr = ecryptfs_setattr,
1206         .getattr = ecryptfs_getattr_link,
1207         .setxattr = ecryptfs_setxattr,
1208         .getxattr = ecryptfs_getxattr,
1209         .listxattr = ecryptfs_listxattr,
1210         .removexattr = ecryptfs_removexattr
1211 };
1212
1213 const struct inode_operations ecryptfs_dir_iops = {
1214         .create = ecryptfs_create,
1215         .lookup = ecryptfs_lookup,
1216         .link = ecryptfs_link,
1217         .unlink = ecryptfs_unlink,
1218         .symlink = ecryptfs_symlink,
1219         .mkdir = ecryptfs_mkdir,
1220         .rmdir = ecryptfs_rmdir,
1221         .mknod = ecryptfs_mknod,
1222         .rename = ecryptfs_rename,
1223         .permission = ecryptfs_permission,
1224         .setattr = ecryptfs_setattr,
1225         .setxattr = ecryptfs_setxattr,
1226         .getxattr = ecryptfs_getxattr,
1227         .listxattr = ecryptfs_listxattr,
1228         .removexattr = ecryptfs_removexattr
1229 };
1230
1231 const struct inode_operations ecryptfs_main_iops = {
1232         .permission = ecryptfs_permission,
1233         .setattr = ecryptfs_setattr,
1234         .getattr = ecryptfs_getattr,
1235         .setxattr = ecryptfs_setxattr,
1236         .getxattr = ecryptfs_getxattr,
1237         .listxattr = ecryptfs_listxattr,
1238         .removexattr = ecryptfs_removexattr
1239 };